Post-conviction DNA exoneration is the legal process for using genetic evidence to overturn a conviction after trial and sentencing. If you were convicted of a crime and believe biological evidence could prove you didn’t commit it, you file a motion in the court that entered your conviction asking that preserved evidence be tested at an accredited lab. If the results exclude you and meet the legal standard for a new trial, the court can vacate the conviction. Every state has its own post-conviction DNA testing statute, and federal law provides a parallel framework for people convicted of federal offenses. The process is more accessible than many people assume, and more procedurally demanding than simply asking a lab to run a test.
Who Qualifies to Request DNA Testing
For federal convictions, 18 U.S.C. § 3600 governs the request.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing If you were convicted in state court, your state’s statute controls, but most state laws share the core requirements the federal statute spells out. All 50 states now have some form of post-conviction DNA testing law.
To qualify under the federal statute, you have to meet several conditions at once.
You must swear under penalty of perjury that you are actually innocent of the offense. This is not a formality. A false innocence claim can trigger a mandatory minimum of three years in prison, served on top of your current sentence.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing
The biological material you want tested must still exist and still be in the government’s possession. You need to identify the specific items, whether that’s clothing, a weapon, or a sexual assault kit, and the evidence must have been kept under an unbroken chain of custody so it hasn’t been contaminated or tampered with.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing
The testing has to be either new or meaningfully better than what was done before. Either the evidence was never DNA-tested and you did not knowingly pass up the chance to test it earlier, or it was tested and you are now asking for a substantially more powerful method.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing You cannot keep re-running the same test hoping for a different result.
Finally, you have to show the testing could produce new evidence raising a reasonable probability that you did not commit the offense. Your motion must set out a theory of defense and connect the requested testing directly to the identity of the perpetrator.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing A general hope that something useful might turn up will not clear the bar.
Whether the Evidence Still Exists
The biggest practical obstacle is usually the evidence itself. Older cases often turn on whether anything testable survived in storage. Federal law tries to prevent that outcome going forward. Under 18 U.S.C. § 3600A, the government must preserve biological evidence collected during the investigation or prosecution of a federal offense whenever the defendant is sentenced to imprisonment.2Office of the Law Revision Counsel. 18 USC 3600A – Preservation of Biological Evidence The definition covers sexual assault kits, blood, saliva, hair, skin tissue, and other biological material.
The duty isn’t absolute. The government can destroy evidence if it notifies the defendant first and the defendant then fails to file a testing motion within 180 days of receiving that notice. Evidence can also be destroyed if prior testing already confirmed the defendant as its source. Where samples are too bulky to keep indefinitely, the government must retain enough material to allow future testing. Knowingly destroying or tampering with evidence that should have been preserved, with the intent to block DNA testing or its use in court, carries up to five years in prison.2Office of the Law Revision Counsel. 18 USC 3600A – Preservation of Biological Evidence
None of this helps if the evidence in your case is already gone. The federal preservation statute applies only to federal cases, and only prospectively. For older state cases, whether evidence still exists is often answered by a phone call to an evidence room.
When Evidence Has Been Lost or Destroyed
If police lost or destroyed the biological evidence before you could test it, your constitutional remedy is narrow. Under Arizona v. Youngblood, the destruction of potentially useful evidence by police does not violate due process unless you can show the police acted in bad faith, meaning they knew at the time that the evidence had exculpatory value.3Supreme Court of the United States. Arizona v Youngblood, 488 US 51 (1988) Negligence, sloppy storage, or indifference to protocol is not enough. That standard forecloses most claims where evidence simply vanished over time.
Filing the Motion
You file the DNA testing motion in the court that entered your original judgment of conviction.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing The motion should identify the specific items of evidence to be tested, explain how testing would support innocence, and include your sworn claim of actual innocence. The court notifies the prosecution and gives the government a reasonable time to respond. Prosecutors can agree to testing or argue that the motion fails the statutory requirements.
The judge then rules on whether every statutory condition is met. If the motion is granted, the court orders the agency holding the evidence to transfer it to an accredited forensic laboratory under supervised chain of custody. The lab performs the testing and sends the report to the court, with copies to both sides.
Deadlines
Federal law creates a soft deadline rather than a hard cutoff. A motion filed within 36 months of conviction is presumed timely. After that window, the motion faces a rebuttable presumption of untimeliness, but a court can still hear it on a showing of good cause, newly discovered DNA evidence, incompetence that contributed to the delay, or circumstances where denial would cause manifest injustice.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing Courts have granted motions filed many years after conviction when circumstances warranted it.
Who Pays for Testing
Most states do not charge filing fees specifically for post-conviction DNA testing motions. The cost of the lab work is separate. The Kirk Bloodsworth Post-Conviction DNA Testing Grant Program provides federal funding that states can use to cover testing costs in eligible cases.4Office of the Law Revision Counsel. 34 USC 40727 – Kirk Bloodsworth Post-Conviction DNA Testing Grant Program Innocence organizations typically pay for testing in the cases they accept. For applicants without organizational backing, access to funding depends on state-level programs and whether appointed counsel can tap into them.
What the Lab Results Trigger
Three outcomes are possible, and they diverge sharply.
If the results exclude you as the source of the biological evidence, you can file a motion for a new trial or for resentencing. The court must grant that motion if the DNA results, considered alongside all other evidence in the case, establish by compelling evidence that a new trial would result in an acquittal.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing The court considers everything, not just what was introduced at trial, so evidence discovered later can factor in.
If the results are inconclusive, the court can order further testing or deny relief. Inconclusive results are common with degraded samples, especially where evidence sat in storage for decades.
If the results confirm you as the source, the consequences are severe. The court denies relief and can hold you in contempt if it finds your innocence claim was false. You can be ordered to pay the full cost of the testing. The finding is forwarded to the Bureau of Prisons, which can revoke good-conduct credit, and to the Parole Commission if applicable.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing A false innocence claim carries that mandatory minimum three-year sentence.
Running an Unknown Profile Through CODIS
When testing produces a DNA profile from someone other than the convicted person, the next step is often running that profile through the Combined DNA Index System, the national DNA database maintained by the FBI. A hit can identify the actual perpetrator, which strengthens the exoneration case substantially.
Only criminal justice agencies can submit profiles to CODIS. Private individuals and private labs do not have direct access. A private lab that performed the testing would need to work through a participating government laboratory to get a profile entered. The profile must also meet technical standards, including analysis at a sufficient number of genetic markers and a match rarity of at least one in ten million, before it qualifies for a national search.5Federal Bureau of Investigation. CODIS and NDIS Fact Sheet
The Standard for Overturning the Conviction
Favorable DNA results do not automatically vacate a conviction. The court evaluates the new evidence against everything else in the record. The central question is whether there is a reasonable probability you would not have been convicted had the DNA evidence been available to the jury.1Office of the Law Revision Counsel. 18 USC 3600 – DNA Testing
The strength of the rest of the prosecution’s case matters a great deal. If the case rested heavily on biological evidence tying you to the scene, and DNA now shows that evidence came from someone else, the conviction is likely to collapse. If the prosecution also had surveillance footage, multiple independent witnesses, or your own admissions, an exclusion from one piece of evidence may not be enough on its own. Cases built on eyewitness identification tend to be the most vulnerable to DNA contradiction, and when genetic evidence directly contradicts the identification that anchored the prosecution’s case, courts frequently find the reasonable-probability standard met.
If the court finds the standard satisfied, it vacates the conviction. The prosecution then decides whether to dismiss charges or retry the case with whatever evidence remains. When DNA definitively points to someone else, especially after a CODIS hit on the actual perpetrator, prosecutors usually dismiss. Moving from a vacated conviction to full exoneration can also depend on whether the jurisdiction requires a formal finding of factual innocence.
Compensation and Record Clearing After Exoneration
Winning your freedom is not the end of the process. Compensation laws exist at both the federal and state levels, with uneven coverage.
Under 28 U.S.C. § 2513, a person wrongfully convicted of a federal crime can sue the United States for damages. The statute caps compensation at $100,000 per year of incarceration for someone sentenced to death, and $50,000 per year for everyone else. To qualify, you must show your conviction was reversed or set aside on the ground of innocence, or that you received a pardon explicitly stating you were innocent and unjustly convicted. You also have to prove you did not commit the charged acts and did not cause your own prosecution through misconduct.6Office of the Law Revision Counsel. 28 USC 2513 – Unjust Conviction and Imprisonment
Roughly 38 states and the District of Columbia have their own wrongful conviction compensation statutes. Annual payment amounts typically run from about $50,000 to $200,000, depending on the state. Eligibility rules vary widely. Some states require a gubernatorial pardon; others require that charges were dismissed on grounds consistent with innocence; several demand a specific judicial finding of factual innocence. A number of states disqualify anyone who pleaded guilty, even if the plea was coerced. States without compensation statutes leave exonerees with no guaranteed payment, and the fallback is a civil rights lawsuit under 42 U.S.C. § 1983 against government officials who violated your constitutional rights.7Office of the Law Revision Counsel. 42 US Code 1983 – Civil Action for Deprivation of Rights These suits can produce larger recoveries but require proving unconstitutional conduct, such as withholding exculpatory evidence or fabricating testimony, and litigation often takes years.
Having a conviction vacated also does not necessarily clean your criminal record. The arrest, charges, and conviction may still appear in background checks unless you take further steps. Some jurisdictions automatically expunge records when a conviction is overturned on innocence grounds; most require a separate petition. Restoration of civil rights, such as voting, jury service, and firearm possession, is often a separate process again, requiring either automatic restoration under state law or a specific application for a certificate or pardon.
Where to Get Help
Pursuing post-conviction DNA testing without a lawyer is extremely difficult. The motions require specific statutory language, strategic framing, and knowledge of forensic science. The Innocence Project and its affiliated organizations across the country review innocence claims, provide representation, and pay for DNA testing in the cases they accept. Many law school clinics also handle these cases. Contacting the Innocence Network organization in your state is the most practical first step. Some state public defender offices have dedicated wrongful conviction units, and the federal Wrongful Conviction Review Program funds nonprofit clinics and public defenders who investigate these claims.