Criminal Discovery in New York: What You Get and When

What does the prosecution have to give you?

Almost everything in its file, automatically, without you asking for it. That is the core of New York’s discovery law, and it is a genuine change from how criminal cases used to work.

CPL 245.20 lists categories the prosecution must disclose without any demand: your own statements, all police reports and investigators’ notes, witness names and contact information, grand jury transcripts, 911 recordings and body camera footage, search warrants and their supporting affidavits, scientific test results including the underlying bench notes, expert credentials, and the criminal records of prosecution witnesses.

Two features do the most work:

• Material held by the police counts as held by the prosecution. The statute deems items in the possession of any New York state or local law enforcement agency to be in the prosecution’s possession. “The police never gave it to us” is not an answer.
• Favorable and impeachment material must be disclosed expeditiously on receipt, not held until the general deadline. That includes anything tending to negate guilt, reduce culpability, support a defense, impeach a prosecution witness, or provide a basis for a suppression motion.

What are the deadlines?

Situation	Deadline	Measured from
Defendant in custody	20 calendar days	Arraignment on the accusatory instrument
Defendant not in custody	35 calendar days	Arraignment on the accusatory instrument
Defense reciprocal discovery	30 days	Service of the prosecution’s certificate of compliance
Prior bad acts the People intend to use	15 days	Before the first scheduled trial date

The clock runs from arraignment, not from arrest and not from the filing of charges. The overarching duty is to disclose as soon as practicable and no later than those dates.

There are extensions. Where material is exceptionally voluminous, or despite diligent good faith efforts is not actually in the prosecution’s hands, the period can be stayed by up to thirty additional days without any motion. Certain categories, such as grand jury transcripts and expert disclosure, carry their own timing rules.

These deadlines were not changed by the 2025 amendments, despite some reporting to the contrary.

Why does discovery decide the speedy trial clock?

Because the two are tied together by statute, and this is the mechanism behind most modern dismissals.

Under CPL 245.50(3), the prosecution is not deemed ready for trial until it has filed a valid certificate of compliance stating it has met its discovery obligations. No valid certificate means no valid readiness, which means the speedy trial clock never stopped running.

That is why discovery disputes in New York are rarely just about paperwork. They are usually about whether the case survives at all. See our guide on how the speedy trial clock runs.

What changed on 7 August 2025?

Substantially, and most published material still describes the old regime.

Amendments enacted in the 2025 budget took effect on 7 August 2025, applying to cases pending on that date as well as later ones.

Before	Now
Disclosure of everything “relating to the subject matter of the case,” on an open-ended list	A closed list, with a catch-all limited to material relevant to the charges or a defense
Compliance reviewed item by item	Courts must assess the totality of the party’s efforts
Prejudice to the defense was not required	Prejudice is an enumerated factor, though no single factor is determinative
Defects raised “as soon as practicable”	35 days to challenge a certificate, with a required conferral
Discovery failures could undo readiness generally	A court may deem the People not ready only if it finds the certificate invalid

The amendments also added a safe harbor: a court shall not invalidate a certificate where the party exercised due diligence and acted in good faith in making reasonable inquiries. Note the conjunction. Good faith alone does not save it.

Did the narrowing cut back on Brady material?

No, and this is the most overlooked part of the 2025 package.

The same legislation added a new section providing that nothing in the discovery article limits the prosecution’s obligations under federal and state constitutional law. The constitutional duty to disclose favorable evidence survives the statutory narrowing intact.

Almost no published commentary on the amendments mentions this.

What is the 35 day rule, and why is it a trap?

Challenges to a certificate of compliance must now be made by motion within thirty-five days of service, where the prosecution has filed an indictment or information beforehand. It replaced an open-ended standard.

Three features make it dangerous for a defendant:

• The motion must be accompanied by an affirmation that the parties conferred in good faith about the specific and particularized matters at issue, and that no accommodation could be reached. Trial courts have made clear that reciting the statutory language is not enough; counsel must describe what was actually done.
• An extension must be requested before the 35 days expire, not after. Courts have held they lack discretion to accept an untimely challenge.
• Mailing does not extend it.

There is a narrow escape where circumstances materially change, including a belated disclosure, or where the party could not with due diligence have known the basis earlier.

One important limit. Missing the deadline forfeits the right to challenge the certificate. It does not extinguish the entitlement to the discovery itself, and courts have ordered disclosure anyway.

Note a local wrinkle: the 35 day clock is triggered only where an indictment or information was filed before the certificate. On a misdemeanor complaint not yet converted, it does not start.

Does late disclosure kill the case?

No, and that belief was already wrong before 2025.

The Court of Appeals held in People v. Bay, 41 N.Y.3d 200 (2023), that the prosecution must exercise due diligence before filing its certificate, that a later supplemental certificate cannot cure a failure to be diligent at the outset, and that the People bear the burden of showing diligence. But it also said plainly there is no rule of strict liability and the statute does not expect a “perfect prosecutor.”

The 2025 amendments codified much of Bay while modifying it. An appellate court has described the criteria as differing, because the amendments added a prejudice inquiry that Bay had rejected. So the accurate statement is that Bay is codified but changed, not that it is untouched and not that it is dead.

What decides these motions is whether the prosecution was diligent before certifying, judged across the whole of its efforts rather than on any single missing item.

What happens when the prosecution does not comply?

The remedies provision was not amended in 2025. A court must impose a remedy or sanction that is appropriate and proportionate to the prejudice suffered, and regardless of prejudice the other side must be given reasonable time to prepare and respond.

The available remedies run a wide range:

• An order compelling further discovery, or an adjournment
• Reopening a hearing, or recalling a witness
• An adverse inference charge, telling the jury it may draw a negative conclusion from the failure
• Preclusion of the evidence, or striking testimony
• A mistrial
• Dismissal, but only after considering all other remedies and where dismissal is proportionate

Where material was lost or destroyed, a sanction is required if the moving party shows it may have contained information relevant to a contested issue.

Does any of this apply to a traffic ticket?

Not automatically. Traffic infractions charged by simplified information, and certain local code offenses carrying no possible jail sentence, sit outside automatic discovery. A defendant in those cases has to move for disclosure, and the court is required to advise of that right at the first appearance.

That carve-out came from the 2022 amendments, not the 2025 ones.

Is the law the same for a case that started before August 2025?

Not necessarily, and courts are genuinely split.

The amendments apply to actions pending on 7 August 2025 and later. But whether the new 35 day challenge window reaches certificates that were served before that date has divided trial courts, with some holding the clock simply started on the effective date and others holding the window applies only to certificates served afterward. No appellate court has resolved it.

On Long Island, trial courts are currently applying both regimes side by side depending on filing dates, so the date a certificate was served genuinely matters.

Where is this litigated in Nassau County?

Mostly in Nassau County District Court, 99 Main Street in Hempstead, where every case is arraigned and where the 20 and 35 day clocks start, including on a felony complaint. Felonies move to Nassau County Court at 262 Old Country Road in Mineola once indicted, and that transition is often what triggers the 35 day challenge window.

Nassau District Court has issued more than one recent dismissal on these grounds, including a January 2026 decision dismissing a case at 92 chargeable days against a 90 day limit, and another where the certificate was held invalid over a 911 recording the prosecution had maintained for months did not exist.

Appeals from District Court go to the Appellate Term for the Ninth and Tenth Judicial Districts, which has been actively deciding these issues.

Related: speedy trial and how the clock runs, suppression hearings, and criminal defense in Nassau County.