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Missouri Man Said DNA Test Could Prove Innocence. He Was Executed Before a Court Ruled.

Lance Shockley died by lethal injection last year. State courts have rejected prisoners’ requests for DNA testing in recent years.

An illustration shows a prison cell in shades of dark teal blue, with an incarcerated person with a ponytail in a beige prison uniform reaching up to a strand of DNA coming down from the ceiling. Some of the horizontal lines that tie the two strands of the DNA together have come undone and fallen on the floor of the cell. In the cell, a bed and a sink and toilet are visible.

Lance Shockley, a man on death row in Missouri, wanted items from the crime scene to undergo DNA testing to potentially prove his innocence. The court scheduled proceedings on his request — but the date set was for two days after his execution.

Patty Prewitt can’t have her DNA tested — and fully clear her name — because her sentence was commuted and she is no longer in prison.

And others, including Lamar McVay, who is serving 30 years for a robbery, can’t even get an answer from the state on his DNA testing request. He's still awaiting a ruling on a motion he filed in September 2022.

Every state has a law allowing people who have been convicted to request DNA testing of evidence in their cases. But in Missouri, courts have made it particularly difficult to access that testing, even for those facing imminent execution, a review of cases by The Marshall Project - St. Louis found.

DNA has played a role in overturning 560 convictions across the nation since 2000, according to the National Registry of Exonerations. Fourteen were in Missouri, though there have been no exonerations here with DNA since 2020.

In recent years, some requests for DNA testing in Missouri were swiftly denied, court records show. Judges sat on others for years, with no apparent ruling.

While imprisoned on a murder case, Patty Prewitt’s DNA testing motion was denied by the courts in 2018. She spent another six years behind bars before the governor commuted her sentence in 2024.

Now 76, Prewitt still has the conviction on her record. The law only allows people in prison to request DNA testing, so she has no legal pathway to be exonerated.

“What harm would it be to find out [the] truth?” Prewitt said. “That’s what I don’t understand.”

Prosecutors tend to oppose testing, citing the original evidence that led to a conviction and stressing the importance of finality in a case. But advocates say testing can correct grave injustices. Several attorneys claim courts in Missouri have misapplied the law by requiring defendants to prove their innocence rather than using a lower standard of proof for mere testing.

Even after some defendants got permission for a new DNA test, the absence of their genetic material at a crime scene was not always enough to overturn a verdict — even in a death sentence. Judges have instead relied on other evidence, like eyewitness identification, and emphasized previous appeals that were denied.

An illustration shows a test tube with a cotton swab resting on it. To the right of that is a small orange tag with the number “1” on it, behind a small ruler and a dark stain. The background of the illustration is sage green.

Facing death

DNA, or deoxyribonucleic acid, is in every person’s cells and consists of a unique genetic code. Police can collect biological material containing DNA, such as blood or skin cells, at a crime scene and compare it to samples taken from a defendant. DNA is often used as evidence in criminal cases.

Missouri passed a DNA law in 2001, allowing people in prison to request testing after they have been convicted.

In order to qualify, a prisoner must show that evidence to test still exists.

In 2022, John Caudill filed a motion for DNA testing on items including a rape kit, the victim’s underwear and blouse, and cigarettes. It was denied in part because he could not demonstrate that authorities had kept the evidence from his 1992 trial. Law enforcement agencies generally do not have to disclose what’s in their property rooms unless there’s a court order.

Speaking recently from a prison in eastern Missouri, Caudill expressed frustration that he never got a clear answer from the sheriff’s office on what items, if any, were saved. Now 61, Caudill, who is serving life without parole, wants to try again, but doesn’t have a lawyer to help him obtain the information he needs.

In Shockley’s death penalty case, a judge ordered evidence to be preserved, according to court documents. His legal team never got confirmation, but presumed it had been maintained, attorney Jeremy Weis said.

Shockley was convicted in the 2005 shooting of highway patrolman Sgt. Carl Dewayne Graham Jr. No eyewitness or forensic evidence placed Shockley at the scene.

A photo shows a bearded White man, wearing a white prison uniform, posing for a portrait.
Lance Shockley was executed in 2025 although some evidence from the crime scene never underwent DNA testing.

In June 2025, the Missouri Supreme Court set the Oct. 14 execution date, prompting a sense of urgency for his legal team. His attorneys wanted pieces from the shotgun shells and other crime scene items, which were never tested for DNA, to be sent to a lab. They also wanted a cigarette butt that had been tested, but with inconclusive results, to undergo more advanced DNA testing.

In court documents, the Missouri Attorney General’s Office fought against any DNA testing, emphasizing the finality of the case, which “serves both the interests of the court and the victims.”

According to the statute, Shockley would have to show that the DNA testing technology “was not reasonably available” at the time of his 2009 trial.

The request went before Carter County Circuit Judge Kacey Proctor, who ruled that testing on the cigarette showed it had been available for the other items. The cigarette couldn’t be retested because the law doesn’t allow repeat testing using the same technology, he said in the July 2025 order.

Meghan Clement, a forensic DNA expert and consultant on Shockley’s case, said that testing has made significant advancements in the past two decades. Tests are now much more sensitive, allowing more information to be obtained with less genetic material.

“What is the harm in doing the testing?” Clement said.

Shockley appealed the denial. The Southern District of the Missouri Court of Appeals scheduled legal deadlines for Oct. 16 and Oct. 22. His team filed a motion to expedite proceedings, saying that with the impending execution, the “request is made in the interest of justice.” It was denied by the appeals court.

The state then executed Shockley by lethal injection on Oct. 14.

Significant questions remained unanswered about his case, his lawyer, Weis, said, including the forensic evidence. The outcome was unjust, he said.

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Less than a month after Shockley was killed, judges and a clerk with the Southern District discussed changing court procedures for death penalty cases. Now, court filings like requests to expedite the process will be reviewed by the entire court instead of only one judge, according to an internal court procedure document obtained by The Marshall Project - St. Louis.

An illustration shows the legs of a person wearing patterned blue, orange and white pajama pants. The background of the illustration is pale purple.

Waiting in prison

Shockley was one of six people from 2022 through 2025 to petition the courts for post-conviction DNA testing, according to a review of records from the State Judicial Records Committee. None was granted DNA testing, including two men who never received a decision on their requests, according to the public docket.

Lamar McVay requested testing for his robbery conviction in a motion filed in September 2022 in Pemiscot County. The judge never ruled.

“I’m pretty much upset because they ignored it,” McVay said from a prison in southeast Missouri.

His attorney, Jennifer Hernandez, said they plan to seek testing again using a different legal mechanism rather than the DNA statute.

Ronald Greer, who was sentenced to life without parole for sex crimes and armed criminal action, sent letters from prison to the court clerk after he filed his DNA motion in July 2023 in Pettis County.

“Can you please tell me the current status of my motion and when the judge might be ruling upon such motion,” he wrote in April 2025.

As of January 2026, he was still waiting for an answer.

“You gotta do your job,” Greer said about the court during a call from Crossroads Correctional Center, about an hour north of Kansas City.

Like Greer, Patty Prewitt’s case involved Pettis County. She was convicted of her spouse’s 1984 murder. She maintained her innocence, saying someone had broken into their home, shot her husband Bill and attempted to sexually assault her.

In 2017, Prewitt discovered police still had pieces of evidence from her case. She requested 10 items be tested, including the pajamas she was wearing.

A judge denied the testing. Brian Reichart, one of her attorneys, said they were “heartbroken.” He believed they met the statute’s requirements.

In an appeal, Prewitt argued that the judge applied a stricter standard for proving innocence to her request for testing, which has a lower standard.

They lost again.

Six years later, former Gov. Mike Parson commuted Prewitt’s sentence. She had spent 38 years in prison.

While free, Prewitt, who lives in the Kansas City metro and is promoting her book on her experience in prison, still has the conviction on her record. She has to check in with her parole officer every three months and can’t leave Missouri without permission. One day in February, her daughter had a doctor’s appointment in Kansas, about 15 minutes away. Prewitt couldn’t go with her.

Now, there is no legal pathway for Prewitt to request any DNA testing because she is no longer in custody.

Most states, including Colorado and New Hampshire, which changed their laws in recent years, do not require someone seeking testing to be in prison, according to tracking by the Innocence Project, a nonprofit that works on exonerations.

A photo shows a Black man with a beard, wearing glasses and a white prison uniform, posing for a portrait.
Marcellus Williams was executed in 2024, even though his DNA was not found on the weapon that killed Felicia Gayle.

In other cases, prisoners in Missouri have received DNA results, but it has not done much good.

In early 2024, St. Louis County prosecutors sided with Marcellus “Khaliifah” Williams, saying he should not be put to death for a 1998 killing in University City. They retested the DNA on the knife used to murder Felicia Gayle. Williams’ DNA was not found.

However, DNA from members of the prosecution team who had handled the weapon was detected. The evidence had been contaminated and was no longer reliable.

Williams was executed in September 2024.

DNA from defendants Rodney Lincoln and Anthony Dixon did not match the evidence in their cases. They remained in prison until a governor commuted Lincoln’s sentence, and Dixon was released on parole.

Rachel Wester, legal director for the Midwest Innocence Project, said if results support an innocence claim, the only relief under Missouri's law is release from prison. In other states, including Kansas and Nebraska, a judge can order a new trial based on DNA results.

Fredrico Lowe-Bey does not believe he’d be found guilty if he went to trial today. He was convicted in a St. Louis rape, and asked for testing in 2001. A judge granted it two years later. Results obtained in 2005 excluded him, but it was not enough proof for the judge to believe he was innocent. Lowe-Bey remains in prison.

Paul Casteleiro, legal director of Centurion, a nonprofit that files claims on wrongful convictions, has worked on Lowe-Bey’s case for more than seven years. They’re now focusing on a victim’s description of the perpetrator, which included freckles, a feature Lowe-Bey doesn’t have. Casteleiro, who has worked on cases in more than a dozen states, said Missouri is particularly hostile to post-conviction relief.

“They simply do not care that an injustice has been committed,” he said.

Tags: Death Sentences Death Row Evidence Capital Punishment Executions Death Penalty St. Louis, Missouri Missouri DNA