What is a Brady violation, and what happens if prosecutors hid evidence in your case? In short: the government is constitutionally required to turn over evidence that helps the defense, that obligation exists whether or not anyone asked for it, and when it’s breached in a way that mattered, a conviction can be undone. The rule is straightforward. Proving a violation happened is where it gets hard, because the evidence that would prove it is, by definition, the evidence nobody disclosed.
The Obligation
The rule comes from a 1963 Supreme Court decision, Brady v. Maryland, and it has been expanded steadily since. The core duty is described plainly in the U.S. Department of Justice’s own Justice Manual: prosecutors must disclose exculpatory and impeachment evidence that is material to guilt or punishment, and because the obligation is constitutional, it applies whether or not the defense requests it.
Three features surprise people:
- It covers impeachment evidence, not just innocence evidence. A deal given to a cooperating witness, a witness’s prior inconsistent statement, or a history of credibility problems all qualify. Evidence that damages the prosecution’s witnesses helps the defense, and it has to be turned over.
- It reaches material the prosecutor never personally saw. Information held by police and others on the prosecution team counts as being in the government’s possession. “The detective didn’t tell me” is not a defense to the obligation.
- Intent isn’t the test. Suppression can be willful or inadvertent. A violation does not require a prosecutor who deliberately cheated.
What Has to Be Shown
Courts generally look for three things: the evidence was favorable to the accused, either because it’s exculpatory or because it impeaches; the government suppressed it, deliberately or not; and prejudice resulted — meaning the evidence was material.
Materiality is the fight in nearly every case. It is not enough that something favorable wasn’t handed over. The question is whether its absence undermines confidence in the outcome. Prosecutors defending these claims typically argue the withheld item was cumulative, trivial, or wouldn’t have changed a thing given the rest of the evidence.
New York law is, in one respect, more protective than the federal floor. Where the defense made a specific request for particular evidence and the prosecution failed to produce it, New York courts have applied a more defendant-friendly standard than the general federal materiality test — asking whether there was a reasonable possibility the result would have differed, rather than requiring the higher showing. Whether that standard applies turns on how the request was framed at the time, which is one reason the old defense file matters so much.
How a Brady Claim Actually Gets Raised
This is where the procedure connects. Suppressed evidence is almost never visible in the trial transcript — that’s what suppression means. So a Brady claim usually can’t be raised on direct appeal, because an appellate court is confined to the record.
The vehicle is instead a motion to vacate the judgment, which is built precisely for facts outside the record. Our explainer on CPL 440.10 motions walks through how that works, including the hearing a court may order when the claim turns on facts never examined in open court.
The practical problem is proof. People rarely discover a Brady violation through a confession; they find it through a later FOIL request, a co-defendant’s file, a civil case against the same agency, a conviction integrity review, or a disclosure that surfaces years afterward in an unrelated matter. Suspecting evidence was withheld is common. Documenting it is the whole battle.
What Happens If a Violation Is Established
If a court finds a material Brady violation, the usual remedy is vacating the conviction and ordering a new trial. It is not an automatic dismissal, and it is not a finding that the person is innocent. The prosecution may retry the case.
A Brady violation can also open a second, separate door, and in practice it splits into two tracks. A civil rights claim against the municipality whose officers or prosecutors were involved can proceed in either state or federal court, since New York State Supreme Court is a court of general jurisdiction and can hear federal civil rights claims alongside state-law claims, which means forum is a strategic choice. That side overlaps with what we cover in our article on malicious prosecution. A claim against the State for having been wrongfully convicted and imprisoned is a different case entirely, brought in the New York Court of Claims, and covered on our wrongful conviction and actual innocence page.
Each of those is its own case with its own standard of proof and its own deadlines. None follows automatically from the others.
If You Suspect Evidence Was Withheld
The useful starting materials are the trial transcript, the defense file from prior counsel including any discovery demands that were made, and the record of what was and wasn’t produced. Those documents establish both what was requested and what arrived — which is the comparison a Brady claim is built on. Prior counsel’s file is often the single most important item and the hardest to retrieve as years pass.
This article is for general informational purposes only and does not constitute legal advice. Speaking with an attorney can help you understand how New York law may apply to your specific situation. Prior results do not guarantee a similar outcome.
Contact Held & Hines LLP
We have successfully handled many cases of this kind, from the motion to vacate through the civil case that can follow. If you believe evidence favorable to the defense was never disclosed in your case, the firm can review the circumstances under our Wrongful Conviction & Actual Innocence and Prisoner’s Rights practice areas and help you understand your options.
If you are currently incarcerated, please reach the firm by phone or mail, or through your facility’s approved email service. If you are writing on behalf of someone who is incarcerated, you can use the contact form.
Frequently Asked Questions
What is a Brady violation?
It occurs when the government fails to disclose evidence favorable to the accused that is material to guilt or punishment. The obligation is constitutional and applies whether or not the defense requested the evidence.
Does a Brady violation require the prosecutor to have acted intentionally?
No. Suppression can be willful or inadvertent. A violation does not require proof that a prosecutor deliberately concealed anything.
Does Brady cover evidence held only by police?
Yes. Information in the possession of the prosecution team, including police, is treated as the government’s, even if the individual prosecutor never saw it.
What happens if a Brady violation is proven?
The typical remedy is vacating the conviction and ordering a new trial. It is not an automatic dismissal and not a finding of innocence — the prosecution may retry the case.
How do you raise a Brady claim if the evidence was never disclosed?
Usually through a motion to vacate the judgment under CPL 440.10, because suppressed evidence is outside the trial record and generally cannot be raised on direct appeal.