True crime has exploded in recent years. In 2014, the addictive first season of Serial had every commuter listening in to Sarah Koenig's investigation into the death of Hae Min Lee, while Steven Avery’s guilt or innocence dominated the public discourse in 2015 thanks to Netflix’s compelling Making a Murderer.
Yet these true crime documentaries are more than just entertainment—for the individuals involved, they shine a light on the investigation and expose its details to a whole new audience eager for answers and justice. In fact, some docs even lead to a major breakthrough in the case.
Here are 9 true crime documentaries that changed the case forever.
The Thin Blue Line (1988)
Randall Dale Adams was sentenced to prison for the 1976 murder of a police officer. Adams, a drifter in the Dallas area, had gotten a ride from David Ray Harris, after his own car ran out of gas. They spent the day together, and then parted ways.
Soon after Harris drove off, he was pulled over by a cop, Robert Wood. Harris shot the officer twice, killing him. Although the police successfully traced the car back to Harris, Harris pointed the finger at Adams. Adams was convicted and sentenced to death.
Later, it was revealed that several of the eyewitnesses to the crime had delivered false testimony. Adams came as close as three days from execution for the crime. Errol Morris’ 1988 documentary, The Thin Blue Line, revealed that Adams had not received a fair trial. Thanks to the film, Adams was released in 1989, after 12 years in prison. He died in 2010.
Related: 10 Books for Fans of True Crime Documentaries That Crack the Case Wide Open
Paradise Lost: The Child Murders at Robin Hood Hills (1996)
Paradise Lost and its two sequels revealed doubts about the guilt of the West Memphis Three, a trio of teenagers who were found guilty of the murder of three boys in Arkansas in 1993. The case was so sensational that several documentaries, movies, and books have been created about the story.
The documentary helped create enough pressure to reopen the case. Paradise Lost 2: Revelations followed the discovery of evidence that the three did not commit the murders. Finally, after increased pressure from appeals and the public, the three teenagers, who after 18 years in prison were now grown men, were released after an Alford Plea.
The Alford Plea allows a defendant to say that the evidence against them will cause a jury to convict them, while maintaining personal innocence. It's a controversial plea for many, and the trio only took it to save the life of one of their group, who was scheduled to be executed.
Capturing the Friedmans (2003)
Capturing the Friedmans came from director Andrew Jarecki, who would go on to direct The Jinx. The documentary tells the story of Arnold and Jesse Friedman, father and son, who were accused of child sexual abuse in the late 1980s. Arnold pled guilty, hoping to spare his son, but Jesse also pled guilty, hoping to avoid a lengthy sentence. Arnold committed suicide in jail in 1995. The documentary raises serious questions about Jesse’s involvement and guilt. Jesse was released on parole in 2001, and still argues for his innocence.
Heir to an Execution (2004)
This heartbreaking documentary was made by Ivy Meeropol, granddaughter of Julian and Ethel Rosenberg. The Rosenburgs were the Jewish couple executed by electric chair they were convicted of spying for the Russians in 1953.
Meeropol approaches the crime from an understandably personal angle, particularly with regard to how the trial and its outcome affected her father and uncle. The men were orphaned after their parents' execution, at the ages of ten and six.
More intriguingly, the documentary also asks tough questions about whether or not her grandparents were in fact both guilty of espionage. Today, it’s widely accepted that Julius was guilty, but the degree of Ethel’s direct involvement is much less clear.
Meeropol grew up thinking both her grandparents were innocent. In the documentary, she admits that Julius was a spy. The government’s pursuit against Ethel seems to have been an intimidation tactic to get the couple to expose more spies, leading to more sinister questions about whether or not their crimes warranted the death penalty.
Related: 16 True Crime Documentaries You Can Stream on Netflix Right Now
Soupçons, or The Staircase (2004)
Michael Peterson said he found his wife lying dead in a pool of blood at the bottom of the stairs in 2001 and told police he thought she had fallen. But the amount of blood at the crime scene and the fact that Peterson had been involved with another woman who also died after a fall down the stairs made police suspicious.
Peterson was found guilty in 2003, but thanks to the documentary The Staircase, which aired in 2004, Peterson’s case received extra attention. In the documentary, Peterson’s four children maintained their belief that their father was innocent.
After a series of appeals, Peterson was granted a new trial in 2011 after it was revealed that one of the prosecution’s star experts, Duane Deaver, had lied on the stand and fabricated evidence. A follow-up series to the documentary also revealed the extent to which evidence had been manipulated.
In 2017, the judge allowed him to enter an Alford Plea, and Peterson was released from prison. To this day, Peterson's guilt or innocence is widely debated. He is currently working on a book about his experience.
Related: The Staircase: The Greatest True Crime Documentary You’ve Never Seen
A Murder in the Park (2014)
This documentary covers the strange case of Anthony Porter. Porter was convicted of two murders in 1982, then released from prison in 1999 after the Medill Innocence Project took on his case. Professor David Protess and his students found and publicized evidence against another man, Alstory Simon, who they said had committed the crimes.
The film reveals that the evidence against Mr. Simon was flimsy at best and that his confession to the crimes was coerced. Subsequently, Simon was also released from prison in 2014. The documentary argues that Porter was in fact the man guilty of the original crime. The City of Chicago was absolved of guilt for imprisoning Porter, after a trial that decided Porter was in fact the killer.
Since the U.S. prohibits repeat trials for the same crime, Porter remains free to this day.
The Jinx: The Life and Deaths of Robert Durst (2015)
No one saw the shocking ending to HBO’s The Jinx coming. Robert Durst stated, while on mic for the show, that he had “killed them all, of course.” Presumably, Durst meant his wife Kathleen Durst, his friend Susan Berman, and neighbor Morris Black. The night before the final episode aired on HBO, Durst was arrested in New Orleans for the murder of Ms. Berman, due to new evidence—a letter that was featured prominently in the documentary.
Durst was taken into custody in the lobby of a Marriott hotel in New Orleans where he had checked in with a fake name. He had stashed thousands of dollars in cash, drugs, a firearm, and more in his hotel room. Maps of Florida and Cuba suggested that Durst may have been planning to flee the country.
His lawyer insists upon his innocence. But upon Durst's arrest, even his brother, Douglas, expressed relief that he had finally been taken into custody. “We are relieved and also grateful to everyone who assisted in the arrest of Robert Durst. We hope he will finally be held accountable for all he has done.” Durst is set to go on trial in January 2020 for the murder of Susan Berman.
Related: How The Jinx’s Robert Durst Got Away with Murder Again and Again
Making a Murderer (2015)
The case against Steven Avery, as chronicled by Netflix’s Making a Murderer, was the chosen topic of conversation at nearly every holiday party in 2015. Whether you think Steven Avery is innocent or not, the series reinvigorated interest in his case. Because of it, Avery was able to secure new legal representation specializing in wrongful convictions, who immediately filed an appeal in early 2016 arguing Avery was denied his right to a fair trial. In October 2018, a second season of Making a Murderer hit Netflix, updating viewers on the state of the case and the multiple appeals that have taken place. In October 2019, Avery's lawyer filed a "new brief at the Wisconsin Appeals court to grant Avery a new trial or evidentiary hearing" in Halbach's murder.
The conviction of Avery’s nephew and co-defendant, Brendan Dassey, also received reinvestigation as a result of the series. Dassey filed an appeal that his confession to the crime was coerced. In August 2016, U.S. magistrate judge William E. Duffin ruled that Dassey's confession had indeed been coerced. A Federal Appeals court upheld a ruling that Dassey’s confession was involuntary and that investigators had violated Dassey’s rights. However, in June 2018, the Supreme Court of the United States declined to hear Dassey's case. In October 2019, Dassey’s legal team initiated a campaign to persuade Wisconsin's governor to grant Dassey clemency. The petition requests a pardon for Dassey and his release from prison or commutation of what remains of his sentence. This is likely one of the last remaining options available to Dassey. The Wisconsin Department of Justice will likely respond to the brief by the middle of November 2019.
The Keepers (2017)
Netflix’s latest true crime series tells the story of the still unsolved 1969 murder of Sister Cathy Cesnik. The Keepers offers up the theory that Cesnik discovered her students at Keough High School were being sexually abused by Father Joseph Maskell. They then propose that someone acting on behalf of the church, or even Maskell himself, murdered Cesnik to silence her.
Maskell died in 2001. His body was exhumed in February of this year to test his DNA against evidence collected at the crime scene—it was not a match. The church also insists that no reports of Maskell’s abuse were ever brought to their attention.
The powerful story behind The Keepers has many pursuing their own investigations on Maskell, the alleged victims, and, of course, justice for Cathy Cesnik. The Archdiocese of Baltimore broke its many years of silence on the subject as a result of the documentary, when a church representative spoke out on a Reddit AMA with series director Ryan White. When White said the person he’d most like to hear from was the Archdiocese, a user called ArchBalt responded, claiming they could not share any information with White on Maskell because of privacy and confidentiality laws. BuzzFeed reports that this user was later confirmed to be a church representative.
Sister Cathy’s case remains open, but many, including the police, believe that The Keepers will help bring the truth to light.
Related: Netflix’s “The Keepers” is Your Next True Crime Obsession
Featured still from "The Keepers" via Netflix