# *Matthews v. Louisiana*

Louisiana is no stranger to violating the constitutional duty to disclose exculpatory evidence to criminal defendants.

August 31, 2026 • Legal Briefs 

By [Laura Bondank-Harmon](https://www.cato.org/people/laura-bondank), [Dan Greenberg](https://www.cato.org/people/dan-greenberg), and [Matthew Cavedon](https://www.cato.org/people/matthew-cavedon) 

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Louisiana is no stranger to violating the constitutional duty to disclose exculpatory evidence to criminal defendants. In fact, half of the Supreme Court’s decisions reversing convictions on this basis come from Louisiana. Juan Matthews’s case is yet another entry in that troubling record and a further example of how Louisiana state courts are failing to uphold the Constitution’s guarantee of a fair trial.

Juan Matthews was wrongfully convicted of murder in 1992 after the State withheld a substantial amount of exculpatory evidence. Over 30 years into his prison sentence, a records request revealed previously undisclosed police files. These files “supplied an eyewitness who described a different man fleeing the scene, showed that the State’s central eyewitness may not have seen the shooting as she claimed, and revealed that a witness who did not have a prior relationship with the victim or his family was shown Matthews’s photograph but did not identify him as the suspected shooter.”

Upon learning of this evidence, Mr. Matthews applied for post-conviction relief under the Supreme Court’s decision in *Brady v. Maryland* (which requires prosecutors to disclose exculpatory evidence). In a cursory three-and-a-half-page decision, the district court acknowledged that the State failed to disclose evidence but denied Mr. Matthews relief. The Louisiana Court of Appeals denied relief and the Louisiana Supreme Court declined review.

Cato filed an amicus brief supporting Mr. Matthews’s effort to secure U.S. Supreme Court review. Prosecutors face almost no consequences for withholding exculpatory evidence—even in bad faith. This crisis of accountability, coupled with the desire to obtain high conviction rates, encourages noncompliance with *Brady* and results in wrongful convictions. Louisiana exemplifies this crisis, with a near-total absence of accountability for prosecutors and a state judiciary that is reluctant to grant relief.

Robust enforcement of *Brady* is all the more necessary considering the prevalence of plea bargaining. Although the jury trial is foundational to our criminal justice system, more than 97% of convictions come from guilty pleas. Federal and state appellate courts are conflicted over how *Brady* applies to plea bargaining, meaning many defendants are foreclosed from raising *Brady* claims by virtue of having pleaded guilty. But even when courts require pre-plea evidentiary disclosures, prosecutors rely on other mechanisms—like appeal waivers—to ensure that defendants cannot later challenge their convictions because of a *Brady* violation.

This scrutiny-free zone will only expand if *Brady* is not rigorously upheld in the trial context. If defendants lack confidence that any trial they receive will not be fair due to the government hiding exculpatory evidence, they will be even more likely to plead guilty. Reversing the decision below will not only afford Mr. Matthews a fair trial—it will reinforce that *Brady* compliance is essential to the integrity of the criminal justice system.

[![Matthews v. Louisiana_pubcover](/sites/cato.org/files/styles/serial_cover_phone/public/2026-08/Matthews%20v.%20Louisiana_pubcover.jpg?itok=ogtzYeTj)](https://www.cato.org/sites/cato.org/files/2026-08/Matthews%20v.%20Louisana_final.pdf) 

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##### *Matthews v. Louisiana* 

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##### About the Authors 

[![Laura Bondank cropped](/sites/cato.org/files/styles/author_picture/public/2026-04/Laura%20Bondank%20cropped.jpg?itok=5E-kUNAw)](/people/laura-bondank) 

##### [Laura Bondank-Harmon](/people/laura-bondank)

Legal Associate

[![Dan Greenberg cropped](/sites/cato.org/files/styles/author_picture/public/2025-03/Dan%20Greenberg%20cropped.png?itok=Ze7HzJaI)](/people/dan-greenberg) 

##### [Dan Greenberg](/people/dan-greenberg)

Senior Legal Fellow

[![Matthew Cavedon-cropped](/sites/cato.org/files/styles/author_picture/public/2025-11/Matthew%20Cavedon-cropped.jpg?itok=SqrUdWTd)](/people/matthew-cavedon) 

##### [Matthew Cavedon](/people/matthew-cavedon)

Director, Project on Criminal Justice, Cato Institute

[![Creative Commons License](/build/cato_2020/images/creative-commons.svg)](http://creativecommons.org/licenses/by-nc-sa/4.0/) 
This work is licensed under a [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-nc-sa/4.0/). 

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