When New Facts Defeat Preclusion in De Facto Takings: Commentary on HRT Enterprises v. City of Detroit

I. Introduction

This commentary examines the Sixth Circuit’s published decision in HRT Enterprises v. City of Detroit, Nos. 23‑1847/1855 (6th Cir. Dec. 22, 2025). The case sits at the intersection of three difficult areas of constitutional and procedural law:

Ripeness and “finality” in federal takings litigation;
The preclusive effect of prior state-court takings litigation (res judicata and collateral estoppel) after Williamson County and Knick;
Substantive de facto takings doctrine under the Fifth Amendment, and the valuation of just compensation.

HRT Enterprises (“HRT”), an owner of industrial property adjacent to Detroit’s Coleman A. Young International Airport, claimed that the City of Detroit (“City”) effectively destroyed the value and usability of its land through a long-running pattern of airport-related activities and non-actions, without ever formally condemning it. After multiple failed state and federal suits, a federal jury ultimately awarded HRT nearly $2 million. The City appealed on ripeness, preclusion, liability, trial management, and damages; HRT cross-appealed on the remittitur that reduced an initial $4.25 million jury award.

The Sixth Circuit (Judge Griffin, joined by Judge Mathis) affirmed across the board, while Judge Thapar dissented, concluding that Michigan’s broad res judicata doctrine barred the federal suit entirely.

Doctrinally, the opinion is important in at least three ways:

It applies the Supreme Court’s “relatively modest” finality requirement in Pakdel to a slow‑developing de facto takings claim, emphasizing that municipalities cannot exploit finality to evade takings liability through inaction.
It clarifies how “new material facts” can defeat state-law claim and issue preclusion in de facto takings cases, despite prior adverse state judgments, and does so over a vigorous dissent emphasizing strict adherence to Michigan res judicata law.
It reaffirms and extends the Sixth Circuit’s earlier de facto takings precedent in Amen v. City of Dearborn, recognizing liability without a formal condemnation or physical invasion where a sustained governmental course of conduct effectively strips property of all or essential use.

II. Factual and Procedural Background

A. The Property and Airport Context

In 1984, HRT purchased an 11.8‑acre parcel on Detroit’s east side, adjacent to the Coleman A. Young International Airport. About 20% of the parcel lies within the airport runway “visibility zone” governed by Federal Aviation Administration (FAA) height restrictions under 14 C.F.R. § 77. Those regulations significantly constrain building heights near runways absent an FAA waiver. To comply fully with the FAA standards without a waiver, the City would need to acquire HRT’s property.

The City had already embarked on a long-term airport safety and expansion program, including acquiring nearby residential properties in an area known as the “Mini-Take” area. HRT’s property, which included an industrial building of roughly four acres, initially had tenants but became fully vacant after the last tenant closed in late 2008. Thereafter, the site suffered extensive vandalism and dumping, and its condition deteriorated.

B. The Early Litigation: 2002–2009

The litigation history is unusually protracted:

2002 Michigan state lawsuit. HRT and its tenants brought an inverse condemnation action in state court alleging a de facto taking. In 2005, a Michigan jury found no taking. The Michigan Court of Appeals affirmed, and the Michigan Supreme Court denied leave in 2008. See HRT Enters. v. City of Detroit, 745 N.W.2d 786 (Mich. 2008) (mem.).
2008 federal lawsuit. HRT then sued in federal court, asserting new facts post‑2005. The district court dismissed without prejudice under Williamson County Regional Planning Commission v. Hamilton Bank, 473 U.S. 172 (1985), because HRT had not yet pursued just compensation in state court based on those new facts.
2009 second Michigan lawsuit. To satisfy Williamson County’s then‑mandatory exhaustion requirement, HRT filed a second state inverse condemnation suit on July 6, 2009. The state trial court dismissed on res judicata grounds, holding that the 2002 action barred the new claims. The Michigan Court of Appeals affirmed, concluding that no new facts distinguished the 2009 claim from the 2002 case. HRT Enters. v. City of Detroit, 2012 WL 3055221 (Mich. Ct. App. July 26, 2012) (per curiam). HRT did not seek review in the Michigan Supreme Court.

By that point, HRT had:

Lost on the merits (jury verdict of “no taking”) in its 2002 state suit;
Had its 2008 federal action dismissed without prejudice for failure to exhaust state remedies;
Had its 2009 state suit dismissed as res judicata based on the 2002 case, with the appellate court holding that there were no new facts.

C. The 2012 Federal § 1983 De Facto Takings Suit

In August 2012, HRT filed the federal action that culminated in the present appeal, asserting a de facto taking under 42 U.S.C. § 1983. The City moved to dismiss (and for summary judgment) on two principal grounds:

Exhaustion/ripeness under Williamson County; and
Preclusion (claim and issue) based on the 2002 and 2009 state proceedings.

The district court held that Williamson County’s state-litigation requirement was satisfied, and, critically, it identified fourteen new factual developments since the earlier litigation. These included:

Loss of HRT’s last tenant in late 2008, leaving the property vacant;
Extensive vandalism and dumping, facilitated by poorly maintained adjacent City-owned land;
Repeated public and internal City statements (from 2006 onward) about constructing a replacement runway and acquiring nearby land, including along French Road where HRT’s parcel sits;
The City’s continued acquisition of other properties in and around the Mini-Take area;
A 2010 Purchasing Division announcement that the City intended to acquire all property needed for a replacement runway;
A 2011 incident in which the City caused HRT’s contractor to be arrested for “trespassing” while building a berm on HRT’s land, thereby holding itself out as owner.

On this basis, the district court denied the City’s preclusion motions and allowed the case to proceed.

D. Summary Judgment on Liability and Two Jury Trials on Date and Compensation

HRT then moved for partial summary judgment on liability. The district court’s key findings included:

The City’s capital plans focused on existing runways but its land acquisitions in the Mini-Take area were to achieve compliance with FAA safety standards.

It was “probably not” possible to obtain a permit for a 40‑foot building within the building restriction line on HRT’s land.

On this record, the court held that the City’s conduct amounted to a taking as a matter of law, but it did not decide when the taking occurred. That issue—together with just compensation—went to a jury.

At trial, HRT asserted that the taking occurred on January 1, 2009 (when the last tenant left). The City argued the taking occurred, if at all, on August 13, 2015 (the date of the court’s liability ruling). The jury chose HRT’s date and awarded $4.25 million.

The district court then granted the City’s remittitur motion, reducing the award to $2,008,000 after finding the evidence could not support $4.25 million. The City declined the remittitur, triggering a new trial on damages only. Before the second trial, the City moved (and failed) to dismiss for lack of ripeness. The court instructed the second jury that the taking date was January 1, 2009, and that jury awarded $1,976,820.

The City appealed, challenging:

Ripeness/finality;
Res judicata and collateral estoppel;
The grant of summary judgment on liability (including reliance on unsworn testimony);
Trial management/bifurcation and alleged prejudice from being forced to concede that a taking had occurred; and
Damages and remittitur.

HRT cross-appealed, seeking reinstatement of the first jury’s $4.25 million award.

III. Summary of the Sixth Circuit’s Decision

The majority opinion:

Ripeness: Held HRT’s de facto takings claim was ripe under Article III and takings finality doctrine, because the “permissible uses” of the property were known to a “reasonable degree of certainty” and the City had taken a definitive position not to condemn the property.
Preclusion: Concluded that neither claim preclusion (res judicata) nor issue preclusion (collateral estoppel) under Michigan law barred HRT’s federal suit. While acknowledging that the 2009 dismissal was “on the merits,” the court held that new material facts arising after July 6, 2009 created a distinct claim that could not have been litigated in the earlier actions.
Liability: Affirmed partial summary judgment finding a de facto taking as a matter of law, relying heavily on Amen v. City of Dearborn. The City’s course of conduct—regulatory constraints, property acquisitions, non-maintenance, public statements, and refusal to condemn—effectively deprived HRT of all or essential use of the property.
Timing of the taking: Held that, in a de facto takings context involving gradual governmental conduct, the district court could lawfully resolve liability at summary judgment while leaving the precise date of taking for the jury.
Unsworn testimony at summary judgment: Recognized that the court erred by relying on unsworn hearing testimony but deemed the error harmless because the disputed testimony merely explained maps and regulations whose substance was otherwise undisputed.
Bifurcation / trial structure: Rejected the City’s argument that it was prejudiced by the separation of liability (decided by the judge) from timing and damages (decided by the jury), holding the issues were separable and Rule 42(b) was properly applied.
Remittitur and damages: Held that the district court acted within its discretion in remitting the first jury’s award and setting a $2 million figure based on the credible valuation evidence. HRT’s cross-appeal seeking reinstatement of the $4.25 million award failed.

Judge Thapar dissented solely on preclusion. Applying Michigan’s broad res judicata doctrine and San Remo Hotel, he would have held that the 2009 state-court judgment barred HRT’s federal suit. He rejected efforts to carve out an equitable exception to res judicata based on Knick v. Township of Scott, stressing the Michigan Supreme Court’s strong commitment to finality and the uniform view of other circuits that Knick does not undo earlier state preclusion.

IV. Analysis

A. Ripeness and Finality in De Facto Takings

1. The Finality Requirement: Pakdel, Palazzolo, and Lucas

The majority situates its ripeness analysis within the Supreme Court’s modern takings finality doctrine:

General ripeness principle. Article III limits federal jurisdiction to “cases” and “controversies,” and ripeness bars adjudication of claims that depend on contingent future events. See Thomas v. Union Carbide Agricultural Products Co., 473 U.S. 568, 580‑81 (1985).
Takings finality rule. A regulatory takings claim is “ripe” when the government has reached a “final decision” on how regulations apply to the specific property. Suitum v. Tahoe Reg’l Planning Agency, 520 U.S. 725, 737 (1997); Pakdel v. City & County of San Francisco, 594 U.S. 474, 475 (2021).
Modest requirement. Pakdel emphasizes that finality is a “relatively modest” requirement, satisfied when the government has taken a “definitive position” on how its regulations apply to the property, so that a court can meaningfully evaluate the alleged taking. 594 U.S. at 478.
Avoiding abuse of procedures. Palazzolo v. Rhode Island warns that the government cannot burden owners with “repetitive or unfair land-use procedures” to avoid a final decision. 533 U.S. 606, 621 (2001) (citing Monterey v. Del Monte Dunes).
Prudential, not jurisdictional. The majority relies on Lucas v. South Carolina Coastal Council, 505 U.S. 1003, 1012–13 (1992), to characterize finality as a prudential doctrine—meaning courts have discretion not to enforce it rigidly, especially after long, fully developed litigation.

2. Applying Finality to HRT’s Claim

The City styled its finality argument as a ripeness defect: HRT purportedly relied on hypothetical future events rather than a concrete government decision. The majority disagreed, emphasizing that:

HRT’s tenants were gone and the property was vacant and vandalized;
The City had publicly and internally announced intentions to acquire property for a replacement runway and refused to reopen access roads;
The City continued to purchase surrounding properties while conspicuously not condemning HRT’s parcel;
Crucially, “based on this record, the City has taken a definitive position: it will not condemn the property.”

These facts, the court held, establish that the “permissible uses” of HRT’s land were known to a “reasonable degree of certainty,” satisfying Palazzolo. There was no risk of deciding a purely hypothetical dispute: HRT had already lost all economically viable use of the property as a functioning industrial/leased asset.

The opinion also gives finality a fairness dimension. After “years of protracted litigation, multiple rounds of summary judgment briefing, and two jury trials,” the court deemed it “unfair” for the City to invoke finality as a last‑minute escape hatch. Citing Lilly Investments v. City of Rochester, 674 F. App’x 523 (6th Cir. 2017), it warned that a “rigid” application of finality would allow governments to avoid the Takings Clause “by simply refusing to act or by imposing unfair conditions.”

3. Significance

The ripeness holding is notable for:

Reinforcing that formal denial of permits or formal condemnation is not required for finality; a government’s entrenched refusal to condemn, coupled with binding regulatory constraints and public commitments to a project, can suffice.
Explicitly recognizing that courts may temper finality with fairness concerns in long-running disputes, treating it as a prudential rather than rigid jurisdictional bar.

For property owners, this reduces the risk that municipalities can indefinitely avoid takings review by never issuing a clear, formal decision while steadily eroding property value. For governments, it underscores that prolonged ambiguity and piecemeal obstruction carry real litigation risk.

B. Res Judicata and Collateral Estoppel under Michigan Law

1. Michigan Claim and Issue Preclusion Framework

Under the Full Faith and Credit Act, 28 U.S.C. § 1738, federal courts must give state judgments the same preclusive effect state courts would. The majority applies Michigan law:

Claim preclusion (res judicata). A final judgment bars a subsequent suit when:
1. There was a prior decision “on the merits”;
2. The second suit involves the same parties or their privies; and
3. The matter in the second suit was, or could have been, resolved in the first.
See Adair v. Michigan, 680 N.W.2d 386, 396 (Mich. 2004); Bragg v. Flint Bd. of Educ., 570 F.3d 775, 776 (6th Cir. 2009).
Issue preclusion (collateral estoppel). Under Monat v. State Farm, 677 N.W.2d 843 (Mich. 2004), issue preclusion applies when:
1. A question of fact essential to the judgment was actually litigated and determined by a valid, final judgment;
2. The same parties had a full and fair opportunity to litigate the issue;
3. There is mutuality of estoppel.
Exception for new facts / changed circumstances. Michigan recognizes that claim preclusion does not apply where “the facts change, or new facts develop.” Labor Council, Mich. Fraternal Ord. of Police v. City of Detroit, 525 N.W.2d 509, 511 (Mich. 1994). A later claim may proceed where new material facts create ongoing or different unlawful conduct that could not have been litigated earlier. See Stanislaw v. Thetford Twp., 2021 WL 3027195, at *3 (6th Cir. July 19, 2021).

2. The Sixth Circuit’s Treatment of the 2002 and 2009 State Cases

The majority treats the two prior state suits differently.

2002 suit. The court easily concludes that the 2002 case—decided by a 2005 jury verdict of “no taking”—does not bar the 2012 federal claim because the factual landscape changed dramatically after 2005. The district court identified fourteen significant developments (vacancy, vandalism, City statements, further acquisitions, etc.) that simply did not exist in 2002–2005. Thus, HRT lacked a “full and fair opportunity” to litigate the later de facto taking in that proceeding.

2009 suit. The second state suit presents a harder question. The state trial court dismissed on res judicata grounds, and the Michigan Court of Appeals agreed, holding there were no new facts between 2005 and 2009. The majority concedes that under Michigan law:

An involuntary dismissal is ordinarily “on the merits” for res judicata purposes unless explicitly without prejudice or based on jurisdictional grounds. See Roberts v. City of Troy, 429 N.W.2d 206, 211 (Mich. Ct. App. 1988); Mich. Ct. R. 2.504(b)(3).

Thus, the 2009 judgment is entitled to preclusive effect to the extent it adjudicated a claim based on facts up to July 6, 2009 (the filing date of HRT’s complaint in that case).

The key question becomes: did HRT’s 2012 federal claim rest on new material facts arising after July 6, 2009, such that it is a different “cause of action” under Michigan law?

3. New Material Facts after July 6, 2009

The majority answers “yes,” relying primarily on two developments:

2010 Purchasing Division notice. In March 2010, the City’s Purchasing Division informed the public it intended to acquire all property necessary to build a replacement runway.
2011 arrest incident. In July 2011, HRT hired a contractor to build an earthen berm to deter trespassers. City officials arrested and prosecuted the contractor’s employees for trespassing on “City owned property,” thereby holding the City out as the owner of HRT’s land.

These facts were not part of the record in the 2009 state case; indeed, they post‑date the filing of that complaint. HRT also pleaded that additional relevant events occurred even while its state appeal was pending, but the Michigan Court of Appeals declined to allow supplementation of the record.

Citing Michigan precedent that res judicata cannot bar “fresh litigation” where new facts and changed circumstances alter the status quo—such as in periodic termination proceedings, In re Pardee, 475 N.W.2d 870, 874 (Mich. Ct. App. 1991)—the majority holds that the 2010 and 2011 developments materially changed the nature of HRT’s de facto takings claim. It stresses the slow‑burn character of de facto takings:

“A contrary rule would unfairly prejudice plaintiffs pursuing de facto takings claims, which by their nature often progress slowly over time. That is to say, a municipality is not forever free from takings litigation about a piece of property simply because it had prevailed in a similar suit a decade prior.”

Therefore, the federal claim was not, and could not have been, resolved in the 2009 state proceeding. Claim and issue preclusion did not apply.

4. The Dissent’s Counterpoint on Preclusion

Judge Thapar’s dissent forcefully criticizes the majority’s preclusion analysis. Key points:

All elements of res judicata are satisfied. Under Michigan’s broad res judicata doctrine, the 2009 dismissal was:
- A decision “on the merits” (an involuntary dismissal not labeled “without prejudice”);
- Between the same parties; and
- Concerning a claim that “was or could have been” litigated in the earlier action.
Critical focus on the date of taking. HRT consistently argued in federal court—at summary judgment and at trial—that the taking occurred on January 1, 2009. The jury adopted that date. As the dissent stresses, January 1, 2009 predates both:
- The July 6, 2009 filing of the second state complaint; and
- The 2010 and 2011 events the majority relies on as “new facts.”
From that vantage point, anything that occurred after July 2009 is chronologically irrelevant to whether a taking had already occurred as of January 1, 2009.
No equitable exception based on Knick. HRT argued that enforcing res judicata would be unjust because, under Williamson County, it was forced to litigate in state court before coming to federal court, and Knick later eliminated that requirement. The dissent acknowledges the “Catch‑22” described in Knick but emphasizes:
- Michigan has not applied the “manifest injustice” / public policy exception to res judicata in recent decades and may have abandoned it.
- The Michigan Supreme Court in Schafer v. Kent County has made clear that interests in finality limit the retroactive effect of new legal decisions; normal procedural rules like res judicata still apply.
- Every other circuit to consider the issue has held that Knick does not undo the preclusive effect of prior state judgments.

On this view, the second state judgment should have ended the matter, and the federal court should have dismissed HRT’s 2012 suit in deference to Michigan’s strong preclusion policy.

5. Doctrinal Tension and Practical Lessons

The majority and dissent highlight a tension that future litigants must navigate:

The majority’s approach treats de facto takings as evolving wrongs, where later conduct can transform a previously noncompensable situation into a compensable taking, thereby generating a new cause of action not barred by earlier losses. This is particularly salient where state appellate courts limit the temporal scope of the record.
The dissent’s approach takes the plaintiff’s asserted date of taking as decisive. If the plaintiff claims that the property was taken as of a particular date (here, January 1, 2009), then any earlier state judgment that could have adjudicated that same temporal claim bars later federal litigation—even if further government conduct occurs afterward.

Practically, for property owners:

It is risky to lock in a precise “date of taking” that predates later significant governmental conduct if there are prior state judgments; that choice can fuel preclusion arguments.
To preserve room for future litigation, counsel may frame the taking as a continuing or cumulative process that matures only after later events.

For municipalities:

The case is a warning that winning one takings suit does not immunize future conduct involving the same property—especially if later actions materially change the burden on the owner.

C. Substantive De Facto Takings Liability

1. Legal Standard: Amen v. City of Dearborn and Penn Central

The Fifth Amendment (as incorporated against the states) prohibits taking private property for public use without just compensation. A “taking” need not be formal or physical; government action “short of acquisition may constitute a constructive taking ‘if its effects are so complete as to deprive the owner of all or most of his interest in the subject matter.’” Amen v. City of Dearborn, 718 F.2d 789, 796 (6th Cir. 1983) (quoting United States v. General Motors Corp., 323 U.S. 373, 378 (1945)).

Amen recognized what the Sixth Circuit here calls a “de facto takings theory”—an ad hoc inquiry under Penn Central Transportation Co. v. New York City, 438 U.S. 104 (1978), into whether, as a matter of fairness, “the community, rather than the property owner, fairly should assume the cost of the official action.” 718 F.2d at 794–95.

In Amen, Dearborn engaged in a multi-pronged campaign to induce residents to sell:

Denying and delaying permits;
Discouraging repairs and requiring maintenance beyond code;
Making repeated statements that prices would drop and the area would be cleared;
Posting signs encouraging sales; and
Allowing acquired properties to decay.

The Sixth Circuit held this deliberate course of conduct constituted a taking, even though there was no formal condemnation or physical invasion.

2. The City of Detroit’s Conduct Toward HRT’s Property

The majority finds HRT’s case “resembles Amen,” highlighting:

The airport’s runway visibility and building restriction zones encroach on HRT’s property, requiring FAA waivers for the existing structure and effectively preventing new development above modest heights.
The City has repeatedly and publicly signaled its intention to expand/replace runways and acquire surrounding land, including near French Road and within the Mini-Take area.
The City has acquired many other properties in the vicinity but steadfastly refuses to condemn HRT’s parcel, leaving it functionally isolated.
Access issues (e.g., refusing to reopen McNichols Road) and non-maintenance of adjacent City-owned land have exacerbated vandalism and dumping on HRT’s property.
The 2011 arrests of HRT’s contractor for “trespassing” on land the City represented as its own suggest the City was treating the property as already within its control.

On HRT’s side, the complete loss of tenants and inability to lease or sell the property demonstrate the economic impact. The majority concludes that the City’s combined regulatory and practical actions “denied [HRT] all or an essential use” of the property, satisfying Amen and Penn Central.

The City invoked older Sixth Circuit precedents—Woodland Market Realty Co. v. City of Cleveland, 426 F.2d 955 (6th Cir. 1970), and Sayre v. City of Cleveland, 493 F.2d 64 (6th Cir. 1974)—where de facto takings claims were rejected absent physical invasion or inclusion in an actual redevelopment project. The court distinguishes those cases on the ground that HRT’s property is within the effective redevelopment/safety zone and is meaningfully constrained by the City’s airport-related actions.

3. Reserving the Date of Taking for the Jury

A distinctive feature of the case is the court’s handling of the timing of the taking. Ordinarily:

“A property owner has a claim for a violation of the Takings Clause as soon as a government takes his property for public use without paying for it.” Knick, 588 U.S. at 189.
When a taking occurs by physical invasion, “the usual rule is that the time of the invasion constitutes the act of taking.” United States v. Clarke, 445 U.S. 253, 258 (1980).

But the court notes that in a de facto taking via gradual conduct, “the exact moment of the taking may be less clear.” Citing United States v. Dickinson, 331 U.S. 745 (1947), it stresses that courts should avoid “procedural rigidities” that force owners into piecemeal or premature suits.

Therefore, it saw no problem with:

Granting summary judgment that a taking had occurred; but
Submitting to the jury the factual question of when the taking crystallized, given contested evidence about the property’s decline and the City’s conduct over time.

The City offered no authority suggesting that a court must determine the date of a taking at the summary judgment stage whenever it determines liability.

4. Significance

The liability holding reinforces several points:

A municipality cannot avoid takings liability by keeping property in regulatory limbo while steadily eroding its value and utility; a “deliberate course of conduct” designed to depress value or avoid formal condemnation can constitute a compensable taking.
In “slow‑burn” de facto takings, liability and timing can be analytically separated, with the latter often suited for jury determination.

For local governments, this suggests that long-term planning and partial implementation around privately owned parcels require careful attention to how cumulative effects—road closures, safety zones, acquisition patterns, and representations to the public—impact remaining owners.

D. Use of Unsworn Testimony at Summary Judgment

At the district court’s request, two individuals familiar with the airport—former planning consultant Michael Borta and airport general manager Jason Watt—gave testimony at a hearing to explain complex maps and the FAA’s height regulations. Their statements were unsworn. The district court then relied in part on these explanations in granting summary judgment on liability.

The Sixth Circuit recognizes that this was error under Dole v. Elliott Travel & Tours, Inc., 942 F.2d 962, 968–69 (6th Cir. 1991), which holds that unsworn statements generally cannot be considered at summary judgment. However, the court finds the error harmless because:

The testimony simply clarified technical aspects of maps already in evidence;
The City did not seriously dispute the accuracy of these descriptions; and
No single fact from this testimony was dispositive in the de facto takings analysis, which rested on a broad pattern of conduct.

The ruling serves as a cautionary note to district courts to ensure that any factual material relied upon at summary judgment meets Rule 56’s evidentiary standards (e.g., affidavits, declarations, deposition testimony, or other admissible evidence).

E. Bifurcation, Trial Structure, and Alleged Prejudice

Under Federal Rule of Civil Procedure 42(b), a court may order separate trials of issues “[f]or convenience, to avoid prejudice, or to expedite and economize.” Only one of these factors is needed. The Sixth Circuit reviews bifurcation decisions for abuse of discretion, asking whether:

The issues are indeed distinct;
They can be tried separately without prejudice; and
Separate trials would promote judicial economy.

Here, the district court initially planned to bifurcate liability from timing and damages but ultimately tried them together in the first trial, with liability resolved by summary judgment beforehand. In the second trial (after remittitur), only damages were at issue, and the court instructed the jury that a taking had occurred on January 1, 2009.

The City argued it was unfairly prejudiced because:

It was compelled to concede that a taking occurred on a specific date (January 1, 2009) even though it maintained that no taking ever occurred.
It was barred from presenting the earlier state-court litigation to challenge liability.

The Sixth Circuit rejects these arguments, emphasizing:

The City’s “prejudice” is nothing more than disagreement with an adverse summary judgment ruling on liability.
District courts routinely decide liability as a matter of law and then submit only damages (and, here, timing) to a jury.
Res judicata and collateral estoppel issues—which the City could not reargue to the jury in light of the court’s pretrial ruling—were legal questions properly resolved by the judge.

The court finds the issues of “whether there was a taking” and “when/how much” were sufficiently separable to justify the structure chosen, and the City failed to show actual trial prejudice.

F. Remittitur and Calculation of Just Compensation

1. Standards for Damages Review and Remittitur

A jury’s damages award must stand unless it:

Is beyond the range supportable by proof;
Is so excessive as to “shock the conscience”; or
Results from a mistake.

See Gregory v. Shelby County, 220 F.3d 433, 443 (6th Cir. 2000). A court must view the evidence “in the light most favorable to the awardee” but may remit an award that lacks evidentiary support. See Farber v. Massillon Board of Education, 917 F.2d 1391, 1395–96 (6th Cir. 1990).

2. Evidence of Property Value

At the first trial, valuation evidence included:

Owner’s testimony (Karl Thomas). He valued the property at $5 million but gave no clear, methodology-based explanation for that figure beyond his background in aerospace and real estate.
HRT’s appraiser (Andrew Reed). He valued the property at $3,008,000 as of January 1, 2009, using “comparables” involving improved land and buildings.
Airport consultant placeholder (Michael Borta). A consulting document he prepared for the airport listed a $6 million “placeholder” acquisition cost for HRT’s property. At trial, he disavowed any “specific basis” for that number.
City’s appraiser (Peggy Young). She appraised the property at:
- $3,000,000 in 2002;
- $3,190,000 in 2005; and
- $1,500,000 in 2010.

The first jury awarded $4.25 million—significantly above any supported expert appraisal and relying, if at all, on Thomas’s speculative $5 million estimate or the discredited $6 million placeholder.

3. The District Court’s Remittitur and the Sixth Circuit’s Affirmance

The district court found:

Thomas’s opinion “should have been given no weight” because it lacked any substantive foundation—he did not show that his valuation was based on more than “mere conjecture,” as required even for landowner testimony. See TVA v. Easement & Right of Way Over a Tract of Land, 405 F.2d 305, 307 (6th Cir. 1968).
Reed’s $3,008,000 estimate was “inflated” because his comparables included improved properties, not directly comparable to HRT’s situation.
Borta’s $6 million placeholder was expressly disavowed by its author.

Rejecting those inflated valuations, the court concluded that the $4.25 million verdict was beyond the range of supportable proof and ordered remittitur to $2,008,000, a figure roughly splitting the difference between the credible appraisals.

The Sixth Circuit held that:

It was within the district court’s discretion to discount Thomas’s testimony; while landowners may testify as “skilled” witnesses, some methodological grounding is required.
The judge reasonably rejected Reed’s comparables and the placeholder figure.
Because these higher valuations were properly set aside, the original $4.25 million award was unsupported and remittitur appropriate under Gregory.
Wallace v. FedEx Corp., 764 F.3d 571 (6th Cir. 2014), which instructs courts to identify the maximum figure the evidence can support, does not require courts to adopt the next-highest expert figure mechanically. It addresses how to begin the remittitur analysis, not the precise method or final figure.

Because the second jury’s award ($1,976,820) was consistent with a reasonable range around the $2 million remitted figure, the majority rejected HRT’s cross-appeal seeking reinstatement of $4.25 million.

V. Complex Concepts Simplified

1. Inverse Condemnation and De Facto Takings

Most people are familiar with formal eminent domain: the government files a condemnation action, takes title, and pays just compensation determined by a court. “Inverse condemnation” reverses that posture: the owner sues the government, alleging that the government’s actions (or inaction) have already taken the property in substance, even though the government never filed a formal condemnation.

A “de facto taking” is a species of inverse condemnation in which:

There may be no physical invasion or formal expropriation;
But the government’s regulations and conduct are so burdensome or targeted that they effectively strip the owner of all or essential economic use of the property.

Courts analyze de facto takings case-by-case, looking at the cumulative effect of government conduct rather than a single act.

2. Ripeness and Finality in Takings

Ripeness is about timing: courts will not decide disputes that are too speculative or contingent. In takings law, this evolved into a “finality” requirement: before suing, an owner generally must obtain a final decision from the government on how the regulations apply to the specific property. The underlying idea is:

If the government might still grant a variance or permit, then a takings suit is premature.
But once the government’s position is fixed, and the owner knows what he can (or cannot) do with the land, the claim is ripe.

Pakdel clarifies that the owner need not exhaust every last procedural step; a clear and definitive position by the government is enough. And as HRT Enterprises shows, courts may be reluctant to let governments invoke finality after years of litigation where their position has long been effectively fixed.

3. Res Judicata and Collateral Estoppel

“Res judicata” (claim preclusion) and “collateral estoppel” (issue preclusion) are doctrines that prevent parties from re-litigating matters decided in earlier suits:

Res judicata bars entire claims that were brought or could have been brought in a prior case between the same parties, after a final judgment on the merits.
Collateral estoppel bars only specific factual or legal issues that were actually litigated and essential to a prior judgment.

These doctrines promote finality and consistency, but they can interact awkwardly with evolving facts, as in de facto takings cases. Michigan law allows new litigation when new, material facts change the legal landscape. The majority in HRT Enterprises leans heavily on that principle; the dissent underscores the competing need for finality.

4. Remittitur

Remittitur is a trial court’s power to reduce a jury’s damages award that is unsupported by the evidence. The court offers the plaintiff a choice:

Accept a reduced award; or
Reject it and face a new trial on damages.

Remittitur is not a license for judges to substitute their own valuation preferences; it is limited to correcting awards that go beyond what any reasonable jury could find on the admissible record.

VI. Impact and Broader Significance

1. For Takings Litigation Strategy Post‑Williamson County and Knick

HRT Enterprises illustrates the lasting impact of pre‑Knick litigation. Many owners were forced by Williamson County to litigate in state courts first, thereby triggering state preclusion rules that later blocked access to federal courts, as underscored by San Remo Hotel.

The majority’s path—treating later factual developments as creating a distinct claim—offers one way around that preclusion trap, particularly in gradual, long-run takings scenarios. But the dissent, backed by Michigan’s emphasis on finality, warns that:

Owners cannot assume that changing law (Knick) will reopen closed cases; and
They must be precise and strategic in defining the temporal scope of their takings claims.

Going forward, owners bringing new federal suits after losing in state court will need to:

Identify concrete, post‑judgment factual developments;
Tie those developments to a new or later‑maturing taking; and
Avoid anchoring their claim to a date of taking already covered by the earlier judgment.

2. For Municipal Planning and Airport Expansion

For cities engaged in airport expansions or similar long-term infrastructure projects, the decision sends several messages:

Long-standing uncertainty, selective acquisitions, and publicly announced plans—combined with regulatory burdens—can cumulatively amount to a de facto taking even if formal project funding is not in place.
Allowing acquired parcels to deteriorate while encircling holdout parcels can be powerful evidence of a purposeful scheme to depress values.
Refusing to condemn a parcel while treating it as if it were city-owned (e.g., arresting contractors for “trespassing”) is especially dangerous from a liability standpoint.

3. For the Law of De Facto Takings in the Sixth Circuit

HRT Enterprises solidifies the vitality of Amen and makes clear that:

De facto takings can be established at summary judgment when the record overwhelmingly shows denial of all or essential use, even in the absence of physical invasion or formal condemnation.
Juries may nonetheless play a crucial role in determining the precise timing of such takings and in valuing compensation.

This will influence how trial courts structure takings cases:

Judges may be more willing to decide the existence of a taking as a matter of law, reserving granular factual questions—such as timing and quantum of damages—for juries.
Parties must be prepared for extensive factual development of government conduct over time, not just regulatory text or formal actions.

4. Potential for Further Appellate or Supreme Court Review

The pointed disagreement between the majority and dissent on res judicata—particularly in the context of pre‑Knick litigation—touches an issue where federal circuits have already expressed views: whether Knick should soften the harsh preclusion effects of San Remo. The Sixth Circuit majority here does not invoke Knick directly to override preclusion but instead relies on new facts. The dissent would reject even that move where the asserted date of taking overlaps with the period covered by the state judgment.

Whether the Supreme Court will eventually revisit the interplay between state preclusion rules, San Remo, and post‑Knick federal takings claims remains an open question. HRT Enterprises provides a concrete setting in which those tensions play out.

VII. Conclusion

HRT Enterprises v. City of Detroit is a significant Sixth Circuit decision at the crossroads of property rights, procedural finality, and federalism. It holds that:

A de facto takings claim can be ripe and justiciable where a municipality’s long-running course of airport-related conduct has effectively destroyed the usable value of a property, even without formal condemnation or physical occupation.
Under Michigan law, new material facts—especially in a gradually unfolding regulatory scheme—can defeat claim and issue preclusion arising from earlier state takings suits, allowing a new federal action notwithstanding prior losses.
De facto takings liability may be resolved at summary judgment, with the precise date of taking and just compensation left for the jury.
Courts maintain robust discretion to remit excessive damages awards in takings cases where landowner or expert valuations lack sufficient foundation.

At the same time, Judge Thapar’s dissent underscores the countervailing weight of res judicata and the limits of equitable exceptions, particularly in a state such as Michigan that prizes finality.

Taken together, the opinions in HRT Enterprises offer a comprehensive and nuanced roadmap for future de facto takings litigation in the Sixth Circuit, highlighting both the opportunities and pitfalls for property owners and municipalities engaged in long-term land-use conflicts.