Probable Cause Suffices for Pre-Revocation Detention: Limits of Due-Process in Probation Revocation

Introduction

In Dion Horton v. Administrative Judge Jill Rangos (3d Cir. 2025), a panel of the Third Circuit addressed two central questions in the probation-revocation context:

1. Whether the Due Process Clause requires an explicit necessity or “suitability for release” finding before detaining a probationer between the preliminary and final revocation hearings; and
2. Whether the county’s actual practices—lengthy delays, lack of pre-hearing notice and potential reflex-probable-cause determinations—violate existing due-process guarantees.

Appellants were six probationers detained for an average of 230 days before their revocation hearings in Allegheny County, Pennsylvania. They challenged the system both to establish a new procedural right (a necessity finding before prolonged detention) and to enforce the procedural rules already laid down by the Supreme Court in Morrissey v. Brewer (1972) and Gagnon v. Scarpelli (1973).

Summary of the Judgment

The Third Circuit panel rendered a split decision:

• Count I (New Right): The court held that the Supreme Court’s precedents in Morrissey and Gagnon set out a comprehensive scheme for revoking probation and parole. Because those cases say that a finding of probable cause at the preliminary hearing “is sufficient to warrant the parolee’s continued detention … pending the final decision,” the panel refused to recognize any additional necessity or danger-to-community finding before pre-revocation detention.
• Count II (Existing Rights): On the claim that Allegheny County’s practices violated the process already guaranteed by Morrissey and Gagnon—specifically, notice of alleged violations, a meaningful opportunity to be heard, and a reasonable time limit on detention—the court found genuine disputes of material fact. It reversed summary judgment for the county and remanded for further proceedings on those procedural-due-process claims.

Analysis

1. Precedents Cited

• Morrissey v. Brewer (408 U.S. 471, 1972): Established that parolees have a conditional liberty interest protected by due process and must receive two hearings before revocation—(a) a preliminary, “summary” hearing on probable cause to believe a violation occurred, and (b) a more formal final revocation hearing.
• Gagnon v. Scarpelli (411 U.S. 778, 1973): Applied Morrissey to probationers, confirming that the same two-hearing framework applies.
• Mathews v. Eldridge (424 U.S. 319, 1976): Arising in other contexts, this case provides the three-factor test for procedural-due-process inquiries (individual interest, risk of erroneous deprivation, government interest and burden). Although Morrissey and Gagnon did not invoke Mathews directly, lower courts often use it to evaluate extensions of those probation-revocation rules.
• Pretrial-detention cases (e.g., Gerstein v. Pugh, 420 U.S. 103 (1975); United States v. Salerno, 481 U.S. 739 (1987)) illustrate that, even where probable cause suffices for an initial arrest, the Constitution may require a separate showing of dangerousness or flight risk to justify continued pretrial detention.

2. Legal Reasoning

The panel’s majority reasoned that:

• “Comprehensive scheme” binding: Because Morrissey and Gagnon collectively set out the full constitutional rules governing both preliminary and final probation-revocation hearings, no one part of those decisions can readily be treated as dicta. The Supreme Court’s statement that “a probable-cause determination … is sufficient to warrant the parolee’s continued detention” thus binds lower courts.
• No extension beyond Supreme Court floor: Probationers differ from arrestees—having already been convicted and serving their sentences, their liberty interest is more limited. The Supreme Court expressly held that once an independent hearing officer finds probable cause, “no further showing of need is required.”
• Existing due process still applies: Although no necessity finding is required, the State must still afford probationers the procedures actually mandated by Morrissey and Gagnon. Because the record revealed disputed facts—late or inadequate notice of hearings, the length of detention, and potential blanket policies by certain judges—the panel reversed summary judgment as to those claims.

3. Impact

This decision:

• Closes the door on novel procedural rights for probationers beyond those spelled out by the Supreme Court.
• Reaffirms the centrality of Morrissey and Gagnon as a blueprint for probation-revocation proceedings.
• Signals that defendants seeking expanded due-process protections in analogous contexts (e.g., immigration detention, civil commitment) must look for Supreme Court overruling rather than lower-court innovation.
• Leaves room for future challenges to county practices that stray from the Supreme Court’s minimum requirements, ensuring that disputed fact patterns can still be litigated.

Complex Concepts Simplified

• Conditional liberty interest: Even after conviction, when a person is on probation, the Constitution protects their freedom to live in the community under set conditions. Revoking that freedom “inflicts a grievous loss.”
• Preliminary hearing (Morrissey/Gagnon I): A brief, informal hearing before an independent officer to decide if there is probable cause that a probation condition was violated. If so, the probationer may be held for a “reasonable time.”
• Final revocation hearing (Morrissey/Gagnon II): A more formal proceeding—notice in writing, disclosure of evidence, right to cross-examination—before a neutral body that decides whether to revoke probation.
• Reasonable time limit: While the Court allowed pre-revocation detention “for a reasonable time,” it gave no bright-line rule. What is “reasonable” depends on local practices, availability of hearing dates, and the county’s compliance with basic procedural guarantees.
• Dictum vs. holding: A court’s “holding” is the rule actually decided in resolving the dispute before it. “Dicta” are comments not essential to that resolution and carry no binding weight on future cases.

Conclusion

Dion Horton v. Rangos underscores that probationers possess a protected liberty interest, but only the process that the Supreme Court has already prescribed. No additional “necessity” or “danger-to-community” finding is required before detaining a probationer between hearings, so long as an independent officer has found probable cause to believe a probation condition was violated. At the same time, counties must still comply strictly with the procedural safeguards of Morrissey and Gagnon: timely and adequate notice of hearings, meaningful opportunities to be heard, and detention no longer than reasonably necessary to hold the final revocation hearing. Procedural-due-process challenges to unlawful local practices thus remain viable, even as the constitutional floor is firmly fixed.