Tang v. Guo (2025 MP 11): Reasonable Certainty in Unjust Enrichment and Liberal Construction of Fraud Pleadings in Parol Evidence Disputes

I. Introduction

The Supreme Court of the Commonwealth of the Northern Mariana Islands (“CNMI”) in Tang v. Guo, 2025 MP 11, addressed a complex property and contract dispute arising from an attempted transfer (or apparent transfer) of leasehold interests. The case sits at the intersection of contract law, the parol evidence rule, fraud pleading standards, unjust enrichment, and equitable remedies.

Formally, the dispute centered on whether a written lease assignment constituted a valid and enforceable contract, the admissibility of parol evidence under the fraud exception, and the proper measure of unjust enrichment where a fraudulent or sham transaction is unwound. Substantively, the case concerned whether a businessman (Tang) could retain money and benefits obtained through what the trial court and Supreme Court both ultimately deemed a fraudulent scheme involving sham lease assignments and pre-signed rescission instruments.

The opinion is especially important for three doctrinal developments in CNMI law:

Pleading and fraud/parol evidence: The Court held that even where a party does not expressly plead “fraud” as an affirmative defense, factual allegations in a counterclaim that clearly describe fraudulent conduct can suffice to invoke the fraud exception to the parol evidence rule.
Unjust enrichment damages: The Court expressly adopted the rule that unjust enrichment damages, like other damage claims, must be proven with a “reasonable degree of certainty,” and must be adjusted for offsetting benefits (here, rental income).
Post-judgment interest and equitable conditioning of relief: The Court reaffirmed that post-judgment interest runs from the judgment establishing liability (even if damages remain to be quantified), and confirmed that CNMI courts may condition the return of property on satisfaction of a monetary judgment, consistent with American common law equity practice.

The parties were:

Plaintiff-Appellant: Xiaodong Tang – Chinese citizen, leaseholder of nine CNMI properties, including the two at issue: the “Fina Sisu Property” and the “PIC Property.”
Defendants-Appellees: Xuemin Mason and her daughter, Xuan Guo – Mason is a Chinese-born U.S. citizen engaged in real estate; Guo was named as assignee in the lease assignments.

Below, the Superior Court found no enforceable contract, denied Tang’s claims of trespass and breach of contract, but awarded Mason $100,000 in unjust enrichment (a $30,000 “loan” plus $70,000 in repair costs). The Supreme Court:

Affirmed the finding of no enforceable contract and the fraud-based use of parol evidence,
Affirmed the $30,000 unjust enrichment award,
Reversed the $70,000 unjust enrichment component for repairs and ordered a recalculation with offsets for rental income,
Affirmed the accrual of post-judgment interest from the date of the findings of fact and conclusions of law (FFCL), and
Affirmed the conditional return of the properties to Tang upon his satisfaction of the judgment.

II. Summary of the Opinion

The dispute arose out of a set of lease assignment documents executed on June 12, 2019. Tang’s father signed as his “attorney in fact” while Guo signed as assignee at Mason’s direction. The documents purported to sell Tang’s leasehold interests in the two properties to Guo for $250,000, with $30,000 in initial payments and the remainder due in two future installments. At the same time, “Confirmation of Rescission of Assignment of Lease” documents were signed and recorded one minute before the assignment documents.

The parties vigorously disagreed as to the nature of their arrangement:

Tang’s account: The $30,000 transfer from Mason was a down payment on the assignments. Mason (acting through Guo as assignee) was to buy the leases, possibly to “flip” them.
Mason’s account: The $30,000 was an emergency loan to Tang, and the written lease assignments (plus rescission documents) were a sham or temporary arrangement meant to facilitate a sale to a third-party buyer, allegedly necessary because Tang claimed he had legal problems in China and could not transact in his own name.

Mason took possession, made repairs (she claimed $70,000 worth), and rented the properties for $1,500 per month total. When Tang later demanded their return, Mason conditioned surrender on repayment of the loan and reimbursement of repair costs. Tang sued for trespass, breach of contract, promissory fraud, and unjust enrichment; Appellees counterclaimed for breach of an oral contract or, alternatively, unjust enrichment.

The Superior Court:

Denied Tang’s motion to exclude parol evidence about the “real” transaction, invoking the fraud exception to the parol evidence rule.
Found no enforceable contract, due to lack of mutual assent to an actual sale.
Rejected both sides’ contract-based claims (including the counterclaim) as unenforceable or too vague.
Denied Tang’s trespass/ejectment remedies under the doctrine of unclean hands, based on his fraudulent conduct.
Awarded Mason $100,000 in unjust enrichment ($30,000 loan + $70,000 repairs), with post-judgment interest from the date of the FFCL.
Conditioned Tang’s recovery of possession of the properties on his paying the judgment.

On appeal, Tang argued mainly that:

The trial court erred in admitting parol evidence under the fraud exception because fraud was never properly pled as an affirmative defense.
The finding of fraud was clearly erroneous.
The unjust enrichment repair award lacked evidentiary support and failed to account for rental income.
Post-judgment interest should not have accrued from the date of the FFCL.
The trial court abused its discretion by refusing immediate return of the properties despite Tang’s undisputed leasehold title.

The Supreme Court held:

Fraud was sufficiently alleged in the counterclaim (though mislabeled as breach of contract), satisfying notice and particularity standards and allowing use of the fraud exception to the parol evidence rule.
The fraud finding was supported by the evidence, particularly the simultaneous recordation of rescission and assignment documents, and credibility assessments.
The $30,000 was properly awarded to Mason on unjust enrichment grounds, but the $70,000 repair component lacked reasonable evidentiary certainty and must be recalculated after offsetting rental income.
Post-judgment interest properly ran from the date the FFCL established liability, consistent with 7 CMC § 4101 and NMHC v. Flores.
The court properly exercised equitable discretion in denying immediate ejectment/return of possession based on Tang’s unclean hands and in conditioning return of the properties on satisfaction of the judgment, consistent with 7 CMC § 4104 and American common law.

Accordingly, the Court affirmed in part, reversed in part (only the repair-based portion of unjust enrichment), and remanded for further fact-finding as to repair costs and rental income.

III. Analysis

A. Precedents Cited and Their Role

1. Contract Validity and Standard of Review

Pangelinan v. Itaman, 4 NMI 114 (1994) – Cited for the proposition that whether a contract is valid and enforceable is a mixed question of law and fact. The Court applied de novo review to legal interpretations, but reviewed extrinsic evidence and credibility determinations for clear error.
Pangelinan v. Pangelinan, 2024 MP 5 – Reaffirmed that assessment of evidence and determinations of witness credibility are questions of fact reviewed for clear error.
In re Abraczinskas, 2023 MP 12 – Reiterated the “definite and firm conviction” standard for clear error and emphasized deference to the trial court when its findings are rationally supported by the record.

These cases frame the Court’s willingness to defer to the trial judge’s credibility assessments, particularly in choosing to believe Mason’s testimony and disbelieve Tang’s, which was “inconsistent with the physical evidence” and “show[ed] bad motive.” That deference is crucial to understanding why the fraud finding was upheld.

2. Parol Evidence and Fraud

Del Rosario v. Camacho, 2001 MP 3 – Quoted for the basic parol evidence rule as well as the fraud exception: although parol evidence generally cannot contradict a fully integrated written agreement, fraud is a recognized exception.
Kim v. Baik, 2016 MP 5 – Cited as a recent articulation of the parol evidence rule in the CNMI, confirming that prior or contemporaneous oral agreements cannot vary a binding integrated agreement absent an exception.

These cases provided the doctrinal baseline: parol evidence is normally excluded, but may come in if a recognized exception, such as fraud, applies. Tang v. Guo then adds to this framework by elaborating when fraud is sufficiently before the court, even if not perfectly labeled in the pleadings.

3. Pleading Fraud and Unpled Affirmative Defenses

Sablan v. Elameto, 2013 MP 7 – The key case on unpled affirmative defenses and Rule 9(b). In Sablan, the trial court sua sponte raised the affirmative defense of “mistake” even though the term was never used. The Supreme Court reversed, holding that it is not enough that the circumstances could “naturally give rise” to an unpled affirmative defense; the pleadings must at least implicitly or explicitly describe mistake (or fraud) to provide notice.
Seol v. Saipan Honeymoon Corp., 1999 MP 9 – Confirmed that rulings on parol evidence and decisions to raise affirmative defenses sua sponte are questions of law, reviewed de novo.
NMI R. Civ. P. 8(c)(1), 8(c)(2), 8(e) – Rule 8(c)(1) requires fraud to be affirmatively pleaded as a defense; Rule 8(c)(2) authorizes courts to treat a mistakenly labeled counterclaim as a defense (or vice versa); Rule 8(e) mandates that pleadings be construed “so as to do justice.”
NMI R. Civ. P. 9(b) – Requires that “the circumstances constituting fraud” be pled with particularity, but allows “malice, intent, knowledge, and other conditions of a person's mind” to be alleged generally.
Mountaineer Fire & Rescue Equip., LLC v. City Nat'l Bank of W. Va., 854 S.E.2d 870 (W. Va. 2020) – Quoted (via Wright & Miller) to support liberal construction of pleadings: a complaint is sufficient if it suggests entitlement to some form of relief, even if the precise theory and requested relief are not perfectly framed.

Drawing on these authorities, the Court held that Mason’s counterclaim – though captioned as a breach of contract claim – implicitly alleged fraud with sufficient detail to satisfy Rule 9(b) and provide Tang with notice. This allowed the court to treat the counterclaim, under Rule 8(c)(2), as including an affirmative defense of fraud and thus to admit parol evidence under the fraud exception.

4. Unjust Enrichment and Damages Standards

Syed v. Mobil Oil Marianas Islands, Inc., 2012 MP 20 – Provided the three-part test for unjust enrichment:
1. Defendant was enriched;
2. The enrichment was at plaintiff’s expense; and
3. Equity and good conscience militate against allowing retention of the benefit.
Antonio v. Baek, 2023 MP 2; Tano Grp., Inc. v. Dep’t of Pub. Works, 2009 MP 18; Bisom v. Commonwealth, 2002 MP 19 – All stand for the principle that damages must be proven with a “reasonable degree of certainty,” not left to conjecture.
Restatement (Third) of Restitution and Unjust Enrichment:
- § 1 – General statement of unjust enrichment as gain obtained at another’s expense under circumstances that make it unjust to retain.
- § 3 – A person cannot retain benefits obtained by his own wrong.
- § 49 – Enrichment is measured by value to the defendant, not just cost to the plaintiff; courts must avoid double recovery and consider offsets.
Epic Sys. Corp. v. Tata Consultancy Servs. Ltd., 971 F.3d 662 (7th Cir. 2020) – Cited as an example of another jurisdiction applying a reasonable-certainty standard to unjust enrichment damages; the CNMI Supreme Court explicitly adopted that standard.

These authorities undergird two significant holdings:

Unjust enrichment awards must be supported by reasonably certain proof of the value of the benefit conferred.
When the defendant has received other benefits (e.g., rent) connected with the unjust transaction, those must be offset against any restitution award.

5. Post-Judgment Interest

7 CMC § 4101 – Provides that every money judgment bears 3% interest “from the date it is entered.”
NMHC v. Flores, 2006 MP 23 – The Court earlier interpreted § 4101 to mean that interest runs from the judgment that determines liability, even if the amount of damages is later quantified. The rationale is compensatory: once liability is fixed, the plaintiff’s right to damages and interest vests.

By reaffirming NMHC v. Flores, the Court confirmed that in CNMI practice, the “judgment” for interest purposes is the first decision establishing liability, here the September 20, 2023 FFCL.

6. Equitable Relief and Unclean Hands

Rosario v. Quan, 3 NMI 269 (1992) – Set the standard of review for exercises of equitable power as abuse of discretion.
Manglona v. Baza, 2012 MP 4 – Recognized that equitable relief can be denied where a party’s conduct is willful, grossly negligent, or lacking in good faith; essentially a formulation of the unclean hands doctrine.
7 CMC § 4104 – Authorizes the Superior Court, “as justice requires,” to dispose of property in any manner known to American common law.
Rice v. Vaughn, 193 P. 176 (Kan. 1920); City of Houston v. Texan Land & Cattle Co., 138 S.W.3d 382 (Tex. App. 2004) – Both illustrate American common law practice of conditioning the recovery or possession of property on payment of a judgment or compensation.

These authorities justify the Superior Court’s choice to:

Deny Tang equitable relief (ejectment/trespass) because of his fraudulent conduct (unclean hands), and
Condition the return of the properties on his paying the unjust enrichment judgment, as an equitable balancing of interests under § 4104.

B. Legal Reasoning in Depth

1. Fraud and the Parol Evidence Rule: How the Court Got Around the “Four Corners”

Tang’s primary strategic move on appeal was procedural rather than substantive: if he could prevent the court from considering parol evidence of the parties’ oral understandings, the written lease assignment would stand as the exclusive manifestation of the parties’ agreement, strongly favoring his position that a straightforward $250,000 sale existed.

He advanced a two-step argument:

The lease assignments were fully integrated written contracts; thus, the parol evidence rule barred any prior or contemporaneous oral agreements.
The fraud exception to the parol evidence rule could not apply because Appellees never properly pled fraud as an affirmative defense under Rules 8 and 9.

The Supreme Court accepted the first premise as a matter of general law but rejected the second. Its reasoning proceeded as follows:

Step 1 – Identifying the governing rule: Under Del Rosario and Kim, parol evidence is barred unless an exception applies. Fraud is such an exception.
Step 2 – Pleading fraud as an affirmative defense: Rule 8(c)(1) requires fraud to be affirmatively pled. Failure to do so ordinarily waives the defense.
Step 3 – Misdesignation under Rule 8(c)(2): If a party mistakenly labels a defense as a counterclaim (or vice versa), the court must treat it as correctly designated if justice so requires. Here, Mason’s counterclaim, although titled as breach of contract, contained detailed factual allegations that effectively describe fraudulent inducement.
Step 4 – Notice and Rule 9(b) particularity: Relying on Sablan v. Elameto, the Court emphasized that there must be more than a “natural inference” of fraud; the allegations must implicitly or explicitly describe fraudulent conduct. Mason’s counterclaim did precisely that:
- Tang urgently requested a $30,000 loan;
- He claimed he had a buyer and that non-use of his own name was necessary due to legal trouble in China;
- He proposed a nominal transfer to Mason (through Guo) solely to facilitate a short-term sale to a third party;
- He promised to repay the loan from sale proceeds and further promised compensation for any repairs Mason undertook to improve marketability; and
- Once she loaned the money and made repairs, he demanded the properties back.

These detailed allegations describe the “who, what, when, where, and how” of a fraudulent scheme, satisfying Rule 9(b)’s requirement that the “circumstances constituting fraud” be pled with particularity. They also provide fair notice to Tang that he would have to confront allegations of fraud at trial.

Thus, the Court held that:

The counterclaim’s facts, though couched in contract language, sufficiently alleged fraud,
The trial court could treat the counterclaim as including an affirmative defense of fraud under Rule 8(c)(2), and
The fraud exception to the parol evidence rule was properly invoked, allowing consideration of oral agreements and the true nature of the transaction.

2. Substantive Finding of Fraud: Simultaneous Recording and Credibility

Once the Court held that it was proper to consider fraud, the question became factual: Was the trial court clearly erroneous in finding that Tang had engaged in fraud?

The key documentary evidence was the combination of:

Lease assignment clauses stating that:
“[I]f Assignee fails to make any payment to Assignor when due, this Assignment shall be deemed automatically rescinded ... In addition, Assignee has executed a rescission instrument ... and agrees that in the event of Assignee's failure to pay when payment is due, Assignor may unilaterally record the rescission instrument...”
Rescission documents providing that:
“Assignee has failed to make a payment to Assignor when due. Therefore the Assignment has been automatically rescission [sic] ... Assignee acknowledges that neither Assignee nor anyone claiming through Assignee has any interest in ... the Lease ... This Confirmation shall be effective upon its recordation ...”
The undisputed fact that:
- The payments were not due until September 12, 2019 and December 12, 2019, yet
- The rescission documents were recorded on June 12, 2019, before any payment could possibly have been missed, and indeed one minute before the lease assignments themselves were recorded.

Formally, one might argue (as Tang did) that the pre-recorded rescission documents were “legally meaningless” and should simply be ignored. The Court rejected this formalistic view. Instead, it treated the simultaneous recording as compelling evidence supporting Mason’s narrative: from day one, the assignment and rescission were designed to ensure that:

Legal “title” (in the leasehold sense) would appear to move to Guo for purposes of facilitating a sale, but
Tang could, at will and without any real default by Guo, render the assignment “null and void” through pre-recorded rescission,
Allowing him to retain both the properties and any money or improvements they generated.

Coupled with the trial court’s credibility determinations – finding Mason’s testimony “credible, consistent, and in great detail” and Tang’s testimony inconsistent with the physical evidence and indicative of bad motive – the Supreme Court determined that the fraud finding was not clearly erroneous.

Thus, what looked on paper like a straightforward sale was, upon close inspection of timing and surrounding circumstances, a fraudulent device to obtain and retain value (loan funds and repairs) under the guise of a conditional sale.

3. Unjust Enrichment: Loan and Repairs as Restitutionary Relief

Once the contract was found unenforceable and fraudulent, the court’s central remedial task was restitutionary: place the parties, as nearly as equity allows, back where they would have been absent the fraudulent transaction. This is where unjust enrichment principles come to the fore.

a. The $30,000 “Loan”

Tang argued that the $30,000 was simply part of the purchase price; the trial court called it an “emergency loan” and treated it as unjust enrichment. The Supreme Court endorsed the trial court’s view for two reasons:

Factual characterization: Based on the court’s credibility findings and the structure of the overall scheme, it was more persuasive that Mason had extended a short-term loan, with the written assignment operating as a sham or collateral to disguise or secure that loan.
Legal principle: Under the Restatement (Third) of Restitution § 3, a person may not retain benefits obtained by his own wrong. Because the assignment/rescission framework was fraudulent, Tang could not equitably keep the $30,000. Restitution required him to disgorge that amount.

Thus, the $30,000 award was affirmed as a proper exercise of the court’s equitable powers to prevent unjust enrichment.

b. The $70,000 Repair Award and the New “Reasonable Certainty” Rule

The more controversial part of the trial court’s unjust enrichment award was the additional $70,000 for repairs that Mason claimed to have made to both properties. The Supreme Court agreed that some enrichment occurred here: Tang would ultimately regain the properties in a repaired, more valuable condition without having paid for those improvements, which he had encouraged. Equity would not allow him to receive a windfall.

However, the record on the amount of enrichment was thin:

Mason gave oral testimony describing the poor condition of the properties and work done on roofs, walls, windows, doors, and utilities.
She asserted that she had receipts but did not produce them at trial.
No invoices, contractor statements, or independent valuation evidence were presented.

Against this backdrop, the Court took an important doctrinal step:

It noted that in other contexts, CNMI law already requires damages to be proven with a “reasonable degree of certainty.”
It cited other courts, including Epic Systems, applying that same standard to unjust enrichment claims.
It then declared that the CNMI now adopts this principle explicitly for unjust enrichment claims.

This is a new and clear holding: unjust enrichment damages must be supported by evidence sufficient to establish their amount with reasonable certainty, and cannot be based solely on speculative or uncorroborated estimates.

Applying that rule, the Court found:

Mason’s testimony alone, unsupported by documentation, was insufficient to fix a $70,000 figure with reasonable certainty.
Thus, the repair-based component of the award could not stand on the current record.

c. Offsetting Rental Income and Preventing Double Recovery

The Court took an additional, equally significant step by requiring that any restitutionary repair award be offset by rental income Mason received during her possession of the properties. The logic follows Restatement § 49:

Unjust enrichment is measured not purely by the plaintiff’s expenditures but by the net benefit to the defendant.
Mason had exclusive possession and rented out the properties for $1,500/month.
Because the contract was invalid, any leasehold income rightfully belonged to Tang; Mason’s retention of rental income is itself a benefit that partially offsets the value of the repairs.
To allow Mason both full reimbursement for repairs and full retention of rents would be a double recovery, inconsistent with equitable principles.

The Court also rejected Appellees’ waiver argument, noting that Tang had indeed raised the rental offset issue in his proposed findings and the trial record contained testimony about rents.

On remand, the trial court is instructed to:

Conduct further fact-finding to determine, with reasonable specificity:
- The actual amounts expended on repairs (using receipts, more detailed testimony, or industry-standard cost evidence), and
- The total rental income Mason derived from the properties.
Calculate the net enrichment to Tang by reducing any repair-based unjust enrichment award by the rental income Mason collected.

This remedy aligns with the Court’s overall goal: unwind the fraudulent transaction and leave each party neither unjustly enriched nor unjustly impoverished.

4. Post-Judgment Interest from the Date Liability Is Determined

Tang argued that post-judgment interest should accrue only from the date a final numerical judgment is entered, not from the earlier FFCL establishing liability. The Court disagreed, reiterating its prior construction of 7 CMC § 4101 in NMHC v. Flores:

“Judgment” for interest purposes is the judgment determining liability, not necessarily the one quantifying every component of damages.
Once liability is established, the plaintiff’s right to damages (and hence to compensation for lost use of money) attaches.
The purpose of post-judgment interest is to compensate the prevailing party for the time value of money they are effectively forced to “lend” to the losing party while awaiting payment.

Thus, the September 20, 2023 FFCL triggered interest, even though certain components (e.g., the precise amount of repair-related unjust enrichment) might later require recalculation. This approach incentivizes prompt payment and prevents the losing party from profiting by delay.

5. Equitable Relief, Unclean Hands, and Conditioning Possession on Payment

Tang’s final arguments concerned property possession. Although the lease assignments and rescission documents were invalidated, his underlying leasehold title was undisputed. Why, then, should he not have immediate possession?

The Court upheld two distinct equitable determinations:

Denial of trespass/ejectment relief under unclean hands:
- The same fraudulent conduct that justified restitution also justified denying Tang equitable remedies.
- Under Manglona v. Baza, a party acting without good faith (e.g., by orchestrating a fraudulent scheme) is not entitled to equitable relief. Tang could not use the court’s equitable power to immediately eject Mason after having induced her to lend money and improve the properties through fraud.
Conditioning the return of property on payment of the judgment:
- Under 7 CMC § 4104, CNMI courts may dispose of property “as justice requires” in any manner known to American common law.
- U.S. case law (e.g., Rice, City of Houston) recognizes that courts may condition the recovery of land or possession on payment of a judgment or compensation – a classic equitable device to balance competing interests.
- Here, the court allowed Tang to reclaim possession only when he demonstrated ability to satisfy the unjust enrichment judgment. This effectively prevents him from enjoying the improved properties while remaining in default of his restitution obligations.

The Supreme Court found no abuse of discretion in these tailored equitable orders. They are consistent with the core equitable maxim that “he who comes into equity must come with clean hands.”

C. Impact on Future Cases and the Relevant Area of Law

1. Pleading Fraud and the Parol Evidence Rule

Tang v. Guo will have substantial practical consequences for litigators and contracting parties in the CNMI:

Labels matter less than facts: Parties can no longer safely assume that failing to use the word “fraud” bars their opponents from introducing fraud-based defenses or parol evidence, so long as the pleadings narrate fraudulent circumstances with sufficient detail.
Heightened risk for formalistic strategies: Parties who rely heavily on the “four corners” doctrine to bar damaging oral evidence must now consider whether the opposing party’s counterclaim or answer implicitly alleges fraud.
Encouragement of liberal construction: The Court’s reliance on Rule 8(e) (“construed so as to do justice”) and on Mountaineer indicates a preference for substance over form, and for allowing claims/defenses that are factually, if imperfectly, pled to be heard on their merits.

Practitioners should, however, still plead fraud explicitly and with particularity to avoid dispute; but when facing a parol evidence challenge, they may rely on Tang to argue that factually rich allegations suffice to put fraud at issue.

2. Evidentiary Demands for Unjust Enrichment Claims

The express adoption of a reasonable certainty requirement for unjust enrichment damages is a significant refinement in CNMI restitution law:

Claimants will need to present objective evidence of expenditure or value (receipts, invoices, expert valuation, market data), not merely broad estimates.
Courts will be more likely to reject inflated or undocumented restitution claims, especially where the claimed amounts are large and contested.
Defendants will have a clear doctrinal basis to challenge speculative unjust enrichment figures and to insist on proper offsets.

In commercial and real estate contexts, this will likely influence practices such as:

Maintaining detailed records of repair or improvement costs where ownership is disputed or informal.
Documenting rental income and expenses associated with property in contested possession.
Structuring agreements to clarify who bears improvement costs if a deal collapses.

3. Offsets and Net Enrichment in Restitution

By insisting on offsetting rental income against repair expenditures, the Court reinforced that unjust enrichment is about net benefit. Future litigants should expect:

Courts will routinely examine both sides of the ledger – not just what the claimant spent, but also what they gained during the relevant period.
Restitution awards will increasingly resemble accounting exercises, requiring granular evidence of inflows and outflows associated with the disputed transaction.

4. Post-Judgment Interest Strategy

For practitioners, Tang confirms:

The moment a court enters a decision establishing liability (such as an FFCL), interest begins running on all components of the money judgment, even if some amounts still await precise calculation.
Defendants must consider the cost of delay in litigating damage quantification or appealing limited issues, as interest will continue to accrue.

5. Equitable Structuring of Remedies

Finally, Tang demonstrates the CNMI Supreme Court’s willingness to:

Use traditional equitable doctrines (unclean hands, conditional decrees) actively,
Invoke 7 CMC § 4104 to craft property remedies mirroring American common law, and
Favor remedies that unwind wrongful transactions without granting windfalls to either side.

This suggests that in complex property disputes involving mixed legal and equitable claims, litigants should:

Present robust evidence on equitable factors (good faith, reliance, hardship), not just formal legal rights;
Be prepared for conditional or staged remedies (e.g., possession contingent on payment); and
Recognize that formal title may not automatically dictate immediate control where equity cuts the other way.

IV. Complex Concepts Simplified

1. Parol Evidence Rule

The parol evidence rule says that when parties have a final written contract, courts generally will not consider prior or simultaneous oral agreements that would change or contradict the written terms. The idea is that the writing is the final word on their bargain.

However, there are exceptions. One major exception is fraud: if a party claims the written contract was obtained by lies or deception, courts will allow testimony about those lies, even if it contradicts the written document.

2. Fraud Exception to the Parol Evidence Rule

The fraud exception allows a party to introduce evidence that:

The other side misrepresented facts, made false promises, or concealed important information,
These misrepresentations induced them to sign the contract, and
They would not have entered the agreement without those misrepresentations.

In Tang, this exception allowed Mason to testify that the lease assignments were never intended to be a real sale, but a temporary device to help Tang sell to a third party and to secure repayment of a loan.

3. Pleading Fraud with Particularity (Rule 9(b))

Rule 9(b) requires that when a party alleges fraud, they must spell out the “circumstances constituting fraud” with more detail than ordinary claims. Typically this means:

Who said or did what,
When and where it was said or done, and
How it was false or misleading.

But courts are flexible about labels: even if a claim is called “breach of contract,” if it contains detailed facts describing a fraudulent scheme, that can be enough to count as alleging fraud.

4. Unjust Enrichment

Unjust enrichment is a fairness doctrine. It applies when:

One person receives a benefit (money, property, improvements, services),
That benefit came at someone else’s expense, and
It would be unfair for the first person to keep it without paying.

The typical remedy is restitution – returning the value of the benefit to the person who conferred it.

5. Reasonable Certainty in Damages

Courts generally do not award money based on guesswork. The reasonable certainty standard means:

You don’t have to prove the exact amount to the penny, but
You must have enough reliable evidence (documents, data, expert testimony) for the court to make a fair, non-speculative estimate.

In Tang, Mason’s uncorroborated oral estimate of $70,000 in repair costs was not enough; she needed receipts, invoices, or other proof.

6. Offsets in Restitution

An offset means subtracting benefits received from losses claimed. In unjust enrichment:

If you claim $70,000 in expenses, but during the same time you earned $20,000 in rent from the same property,
Courts will often treat your net loss as $50,000, not $70,000.

This prevents you from being paid twice – once by the rent and once by the restitution award.

7. Post-Judgment Interest

Post-judgment interest is interest that accrues on a money judgment from the time the court enters judgment until the judgment is paid. It compensates the winning party for the time during which they were entitled to money but did not have use of it.

In CNMI, it is 3% per year under 7 CMC § 4101 and starts from the judgment establishing liability, not necessarily the final dollar-amount judgment.

8. Unclean Hands and Equitable Remedies

The unclean hands doctrine says:

If you ask a court for an equitable remedy (like an injunction or specific performance) but you have acted unfairly, dishonestly, or in bad faith in connection with the dispute,
The court can refuse to help you, even if you have some legal rights on your side.

In Tang, because Tang orchestrated a fraudulent transaction, the court refused to grant him immediate equitable relief (trespass/ejectment) and instead conditioned his getting the properties back on him first paying what he owed under unjust enrichment.

V. Conclusion

Tang v. Guo, 2025 MP 11, is a significant decision in CNMI jurisprudence. It clarifies and develops several important doctrines:

Pleading and fraud: Facts, not labels, determine whether fraud has been sufficiently alleged to invoke the fraud exception to the parol evidence rule. Detailed factual allegations in a counterclaim can be treated as an affirmative defense under Rule 8(c)(2), satisfying Rule 9(b) and opening the door to parol evidence.
Contract validity and fraud: Apparent formal contracts may be invalidated where surrounding documentation (such as pre-recorded rescission instruments) and credible testimony reveal them to be part of a fraudulent scheme.
Unjust enrichment and damages: The Court explicitly adopts the rule that unjust enrichment damages must be proven with reasonable certainty and must reflect net enrichment after offsets like rental income. The decision signals a more rigorous, evidence-driven approach to restitutionary awards.
Interest and timing: Reaffirming NMHC v. Flores, the Court confirms that post-judgment interest accrues from the judgment establishing liability, incentivizing timely resolution and payment.
Equity and property remedies: By using unclean hands and conditional return of property, the Court showcases its willingness under 7 CMC § 4104 to craft flexible equitable remedies that unwind fraudulent arrangements without rewarding wrongdoing.

At a broader level, Tang underscores the CNMI Supreme Court’s preference for:

Substance over form in pleading and contract disputes,
Fairness and balance in restitution, and
Active, principled use of equitable doctrines to prevent both opportunistic reliance on formal documents and speculative or duplicative restitution claims.

For lawyers and parties in the CNMI, the opinion is both a warning and a guide: fraudulent or sham transactions will not be enforced; parol evidence will be admitted when fraud is properly (even if imperfectly) alleged; and unjust enrichment claims must be proven with careful documentation and will be calibrated to ensure no party is unjustly enriched – or unjustly impoverished – by the court’s decree.