Nicole Harris, Henry Lee McCollum and Leon Brown have lived through their own nightmares of injustice. All three were wrongfully convicted of the heinous murders of children. Combined, they spent nearly 70 years in prison before being exonerated and forced to adapt to a world that had left them behind.

But their cases represent two different eras in the criminal justice system: one in which DNA evidence has reversed some of the most horrific miscarriages of justice of the last several decades—and rightfully dominated headlines about exonerations—and a new era that is shining a light on wrongful convictions won by false confessions, unreliable witnesses, bunk science and prosecutorial misconduct.

In late September 1983, half-brothers McCollum and Brown—then 19 and 15, respectively—were arrested for raping and murdering 11-year-old Sabrina Buie, who had been found in a soybean field in Red Springs, North Carolina, beaten with sticks and suffocated with her own underwear.

The crime was so vicious and wicked that in 1994, Supreme Court Justice Antonin Scalia—in response to then-Justice Harry Blackmun's declaration that he opposed capital punishment—cited Buie's murder as a case that clearly warranted the death penalty.

"How enviable a quiet death by lethal injection compared with that," Scalia wrote.

However, no physical evidence linked either of the brothers to the crime. They were questioned without a lawyer or parent present. And McCollum only confessed after he was interrogated for five hours and promised by investigators that he could go home if he signed a confession. Both his and Brown's confessions were unrecorded and instead handwritten by police.

McCollum and Brown, who are both intellectually disabled, were convicted and sentenced to death.

More than 20 years later, Nicole Harris' boyfriend found her 4-year-old son Jaquari in their Chicago home asphyxiated by an elastic band from a fitted bed sheet wrapped around his neck. Police thought Jaquari's death could have been the result of foul play and, thus, interrogated his mother for more than 27 hours, during which they allegedly threatened her, physically assaulted her, and denied her food and water.

Eventually, investigators induced Harris—distraught and exhausted—into a false, videotaped confession. After being charged with first-degree murder, a jury convicted Harris in October 2005 and sentenced her to 30 years in Illinois' Department of Corrections.

"Sometimes (defendants) confess because they think because they're innocent that it will all get straightened out later," says Alison Flaum, an attorney with Northwestern University's Center on Wrongful Convictions, who helped get Harris' conviction overturned. "Innocence can work against an innocent person that way. People trust you are telling the truth if you confess."

What the jury never heard before convicting Harris was investigators' questioning of Jaquari's 6-year-old brother Diante, who told police that Jaquari liked to pretend he was Spiderman, wrap the fitted sheet's elastic band around his neck and jump off the bed. Diante was barred from testifying in court because the judge decided he was incompetent.

But earlier this year—more than eight years after her conviction— Harris' sentence was finally overturned after it was learned that the medical examiner's office had initially concluded that Jaquari's death was accidental before changing its ruling to homicide upon learning of Harris' confession, and she was released from prison.

And unlike the majority of overturned convictions that have garnered headlines in the past decade, Harris was not exonerated by DNA evidence.

"This was a case of investigator tunnel vision," says Flaum, adding that police had made up their mind before they even began interrogating Harris. "They extracted a confession from a grieving mother."

According to data from the National Registry of Exonerations (NRE), a joint project of Northwestern’s School of Law and the University of Michigan Law School that first began recording wrongful convictions in 2012—and has documented at least 1,408 cases from the last 25 years—the prevalence of overturned convictions that don't rely on DNA evidence is trending upward.

In 2013, the registry documented 87 exonerations, the highest ever in a single year, according to the NRE. Of those, DNA evidence played a role in only 18 cases. That's down from 23 in 2005 and 20 in 2012.

The NRE is seeing more cases like that of Joseph Awe, a Wisconsin pub owner who was found guilty of burning down his business in 2006 to collect on a $200,000 insurance policy and spent three years in prison.

A review of fire experts' testimony concluded their opinions were not neutral—they had been hired by the insurance company—and an independent investigation concluded the fire that destroyed the 130-year-old building was caused by electrical problems.

"I would hate for anyone to go through what I have gone through," said Awe, whose conviction was overturned and he was released from prison just two months before his 3-year conviction was set to expire.

Now-debunked arson science is also to blame for keeping a Pennsylvania man behind bars for 24 years in the death of his own daughter, before a federal judge was forced to throw out 79-year-old Han Tak Lee's 1989 conviction and allow him to walk free.

David Gavitt is now suing Ionia County, Michigan, after he was convicted of setting his own home on fire and killing his wife and two daughters in 1985 and then spent 26 years in prison. The prosecution's case of "suspicion and conjecture," according to Gavitt's attorney, is to blame for his wrongful conviction.

Davitt was exonerated through independent fire testing and released in 2012.

In Louisiana, Reginald Adams spent 34 years in prison for a murder he didn't commit because of—according to the New Orleans district attorney- prosecutorial and police misconduct, before being released and exonerated in May 2014. In Illinois, Rondell Sanders spent 10-12 hours a day, seven days a week studying law books to overturn his own murder conviction and secure his release in July 2014 after spending 20 years in prison.

"He gathered all of the evidence and then used it to overturn his conviction," said Russell Ainsworth, Sanders' attorney with the Exoneration Project. "There was no fluke; this is the result of years of dedicated hard work and some expert lawyering that he did by simply reading a few books."

Despite the prevalence of those cases, there have been proportionately fewer overturned convictions for the most violent crimes. A third of the total exonerations in 2013 did not involve charges of murder or rape, nearly double the proportion of such cases in 1989, and an increasing number of exonerations involve less serious charges.

In 27 of the cases reported by the NRE in 2013, a crime never even took place. Almost half of those were for nonviolent charges, mostly drug convictions.

According to Justin Brooks, a professor at California Western School of Law and project director of the California Innocence Project, the registry is beneficial in uncovering where the system has failed innocent people, and it can be used to spark legislative and judicial reforms.

"It shines the light on the entire criminal justice system," Brooks says. "If we're making mistakes in the biggest kinds of cases, such as death penalty cases, what does that say about lower-level crimes?"

The downward trend in DNA-related exonerations is owed, experts say, to the widespread availability across the country of DNA testing, which now often clears the wrongfully accused before they are forced to prove their innocence to a jury.

But for Henry Lee McCollum and Leon Brown, DNA didn't set them free until after they each spent three decades in prison.

Sabrina Buie's body was found in a sort-of "lovers' lane" area of Robeson County, N.C., according to district attorney Joe Freeman Britt, who prosecuted McCollum and Brown in the 1980s. "Beer cans, condoms and cigarettes," Britt says, were all over the ground.

Not until July 2014 did the North Carolina Innocence Inquiry Commission finally match the DNA from one of those cigarette butts to Buie's real killer: Roscoe Artis, "a convicted rapist and murderer who lived less than 100 yards from where (Buie's) body was found," according to a statement from McCollum's and Brown's attorneys.

Artis is already serving a life sentence for a similar murder he committed just weeks after he killed Buie.

Three days before McCollum's and Brown's trial in 1984, police reportedly requested that a fingerprint from the scene be tested to see if it matched Artis'. But the test was never performed, and Britt never revealed the fingerprint request to the defense.

Britt was once listed in the Guinness Book of World Records as the "deadliest prosecutor" for sending almost 50 defendants to death row during his tenure. According to the New York Times, almost all of those cases have been overturned, including McCollum's and Brown's.

On September 3, 2014, McCollum and Brown were released from prison after a state judge ordered them both freed. Their exonerations have been a lightning rod for death penalty opponents who want capital punishment outlawed.

"Ain't no anger in my heart. I forgive those people," McCollum told reporters after being released. "I don't like what they done to me and my brother because they took 30 years away from me for no reason, but I don't hate them."

Both men, now middle-aged, will have a difficult adjustment. McCollum's mother and the grandmother who helped raise him died while he was in prison.

Though DNA-related exonerations are on the decline, there are still many more wrongfully convicted still in prison like McCollum and Brown.

"You (still) have a certain number of cases in which DNA testing was never done or was not available, and a lot of those have been worked through —they've been sized up by an innocence project or someone who has requested DNA testing," says Nick Vilbas, executive director of the Innocence Project of Texas. "That doesn't mean it's the end of DNA exonerations. We still have several DNA cases in the process right now."

What follows is just a sampling of recent DNA exonerations from several states across the country.

CONNECTICUT

 In July 2014, Kenneth Ireland told state officials that he wants between $5.4 million and $8 million for being wrongfully convicted of murder and rape when he was 18 and forced to spend 21 years in prison for crimes he didn't commit.

"You never think this is going to happen to you, especially in America," Ireland, now 44, told Connecticut Claims Commissioner J. Paul Vance Jr. in a special hearing. "I figured there was an error being made and that they'd figure this out and it would go away."

But it wasn't until 2009 that DNA evidence finally cleared Ireland in the 1986 death of Barbara Pelkey, a 30-year-old mother of four, in the town of Wallingford. Kevin Benefield, who worked in the same building where Pelkey worked, was ultimately linked to the DNA evidence, convicted and sentenced to 60 years in prison.

Witnesses told a jury at Ireland's trial in 1989 that he had killed Pelkey. Ireland's defense argued that those witnesses had lied to cash in on a $20,000 reward, but he was convicted and sentenced to 50 years.

"As a mother it broke my heart," Ireland's mother, Cherry Cooney, told Vance at the hearing. "It was a wasted 21 years of his life, a senseless waste."

In 2006, James Tillman was released from a Connecticut state prison after serving 18 years and being exonerated of the rape conviction that sent him there. Tillman was paid $5 million by the state legislature for his wrongful conviction.

State Attorney General George Jepsen has said he has no objections to the damages Ireland is seeking.

LOUISIANA

In June 2014, DNA testing overturned Nathan Brown's wrongful conviction for a 1997 attempted rape, of which he was convicted based solely on the victim's misidentification.

Brown, now 40, served 17 years of a 25-year sentence for attempted aggravated rape of a then 40-year-old woman who lived in the same apartment complex as Brown in Metairie, outside New Orleans.

DNA testing, requested by Brown's attorneys with the Innocence Project of New York in December 2013, "identified the source of the biological material as a specific known individual other than Nathan Brown," Brown's attorney Vanessa Potkin wrote in a motion asking that his sentence be vacated and his release ordered.

"Because Nathan Brown is not the source of the male biological material that was tested , he was established by clear and convincing evidence that he is factually innocent of the attempted aggravated rape for which he was convicted."

Upon his release, Brown was the third person wrongfully convicted of rape in Louisiana to be exonerated by DNA evidence and have his conviction overturned with help from the Innocence Project.

In 2012, Darrin Hill was ordered by a New Orleans judge                to be released from a state mental hospital, where he spent the last 20 years for a rape he didn’t commit. In 2011, Henry James was released from Angola,      where he spent 30 years, and his rape conviction was also vacated.

MICHIGAN

On September 8, 2014, Jamie Lee Peterson was released from prison, where he spent the last 17 years, after DNA tests proved that he did not rape and kill a 68-year-old woman.

Peterson was originally convicted after he gave a false confession four months after Geraldine Montgomery was found raped and murdered in her Kalkaska, Mich., home. Some testing of DNA found on Montgomery's body excluded Peterson from the outset, but prosecutors argued in trial that DNA found on her collar—and which could not be tested—was Peterson's.

But tests now connect the DNA to Jason Ryan, who was arrested in fall 2013 and awaits trial. State police say Ryan and Peterson did not know each other.

Also this year, Donya Davis, 36, was released from the Wayne County Jail in Detroit after spending the last seven years at the Lakeland Correctional Facility. Davis has been granted a new trial and was ordered released after DNA testing excluded him from the rape of a Detroit woman in 2006.

According to the Thomas M. Cooley Law School Innocence Project, who helped free Davis, DNA tests "point to another man."

NEW YORK

Seven years after completing a 10-year sentence for a 1998 rape he didn't commit, Tyrone Hicks of Brooklyn was finally exonerated in May 2014 thanks to DNA testing.

A 27-year-old woman claiming to have been raped, identified Hicks out of a police lineup, and based on her claim alone, he was charged and convicted.

While serving time for a wrongful conviction, Hicks developed diabetes, lost his wife to divorce, and had his hair set on fire by other prisoners.

"This Spanish guy told me that if I lay down and went to sleep, they were going to kill me right there," Kicks told the New York Post about his time in prison.

It wasn't until after his release from prison in 2007 that Adele Bernhard of New York Law School's exoneration clinic had scrapings from underneath the woman's fingernails finally tested and found they didn't contain even a trace of Hicks' DNA.

OKLAHOMA

In July 2014, the Norman Police Department charged Gilbert Harris, 58, with the 1982 rape of a University of Oklahoma student, using the same DNA evidence that ultimately exonerated the man who had been originally convicted of the crime and sentenced to 60 years in prison.

In 1996, after more than 13 years in prison, Thomas Webb, of Oklahoma City, was finally released after a DNA test he fought for excluded him from having raped the OU student. The student misidentified Webb—who was 22 at the time of the crime—as her assailant in a photo lineup.

Though Webb had an alibi and no history of sexual assault, he was still arrested and convicted.

It wasn't until six years after his conviction was overturned that police entered the DNA evidence from the rape case into the national DNA database. In 2006, Harris had a run-in with law enforcement and had his DNA collected. Harris also spent four years in prison after convictions for second-degree burglary and weapons charges in 1991.

Still, Harris wasn't linked to the crime until 2013 after an inquiry by Oklahoma Watch got investigators to reopen the case.

In May 2014, a Tulsa woman who had been convicted of killing her own 3- month-old son based on a forced confession was freed from prison after DNA evidence cleared her of the crime.

Four months after her release, Michelle Murphy was officially declared innocent of the 1995 murder of her son by a Tulsa County district judge when prosecutor Tim Harris moved to vacate Murphy's conviction and attempt to make some sort of amends for the 20 years she spent behind bars.

"The law, the facts, the evidence and the witnesses, as they exist at the present time, as well as the passing of 20 years creates a set of circumstances where the State of Oklahoma does not believe that it can meet its burden of proof at a jury trial of 'beyond a reasonable doubt,'" Harris' motion to vacate read.

According to Murphy's attorneys, the infant was killed by a 14-year-old boy from Murphy's neighborhood who allegedly had a juvenile criminal record. Shortly after Murphy's preliminary trial in 1995, the teenager committed suicide.

If Murphy chooses to file a civil tort claim against the state for its handling of her case, Oklahoma's liability has been capped by lawmakers at $175,000.

TENNESSEE

After serving 11 years in prison for a 1999 rape he did not commit, Randy Mills had all the remaining charges against him related to the crime dismissed in April 2014.

Tennessee's Court of Appeals had already ordered a new trial for Mills in November 2013 based on DNA evidence proving he did not rape his accuser, who was 12 years old and a next-door neighbor of Mills and his two teenage sons when he was charged with raping a child and aggravated sexual battery.

A circuit court judge first dismissed the rape charge for which Mills was convicted thanks to a review of the DNA data by Tennessee's Innocence Project. The Marshall County District Attorney's Office then dismissed the remaining three charges of sexual battery.

"Randy Mills spent more than a decade locked up for a crime that more thorough investigation and careful forensic work would have revealed that he shouldn't have been charged with in the first place," said Innocence Project staff attorney Bryce Benjet.

Mills' conviction was based not only on the 12-year-old's inconsistent testimony, but also after a state lab analyst who performed DNA testing on sperm found on the child's underwear said that Mills "couldn't be excluded" from having committed the crime.

Mills' sex offender registration after his release in 2011 prohibited from seeing his grandchildren and from leaving the state to visit the grave- site of his son, who died while Mills was incarcerated.

TEXAS

Michael Phillips, 57, was officially exonerated on July 25, 2014, by Dallas County's Conviction Integrity Unit after being falsely convicted of raping a 16-year-old girl.

Phillips had already served his 12-year sentence for the crime and had been out of jail since 2002 when DNA testing proved he was not the man who had raped the girl, who identified Phillips as her assailant after seeing a six-person photo lineup.

Phillips agreed to a plea deal in the case in 1990 because he believed that—as a black man accused of raping a white, teenage girl—he would not receive a fair trial. A 2012 study by the National Registry of Exonerations found, in fact, that most rape exonerations due to eyewitness misidentifications involved a white victim and an African-American alleged perpetrator.

"You are a black man. This is a young white girl who has been assaulted. You have an X on your back already. What do you think the chances are if you go before an all-white jury?" Phillips recalls his public defender asking him.

"Aren't you supposed to get a jury of your peers?" Phillips replied.

"Yeah, but it's not going to happen."

Since his release, Phillips had been registered as a sex offender, had trouble finding a job, and was forced to leave the nursing home where he lived—to deal with his sickle cell anemia—after the staff there found out about his sex offender status.

Now, thanks to Texas law, Phillips has been awarded $80,000 for every year he was wrongfully incarcerated—a lump sum of $960,000—and will receive $80,000 annually for the rest of his life. The state also offers exonerees free state-run healthcare and a free education.

"The first thing I am going to do is get a Ford pickup truck and a house. Or I might just hit the road. You got 50 states. I might just hit the road and visit the rest of the country," Phillips says. "I dreamed of going to China and walking on the Great Wall of China."

WASHINGTON, D.C.

DNA evidence trumped hair samples that sent a teenager to prison for 26 years in the 1982 killing of a D.C. woman.

Kevin Martin, now 50, was exonerated in the murder of Ursula Brown after federal attorneys moved to vacate Martin's conviction, citing DNA evidence that contradicts the findings of a once-elite FBI forensic unit that linked Martin to hair found at the crime scene.

Paroled in 2009 and now living in San Francisco, Martin left a D.C. courthouse in July 2014 with his name cleared.

"I am free at last. I am humbled. I never gave up," said Martin, who was sentenced in 1984 to 35 years in prison for manslaughter and robbery after entering an Alford plea.

Martin's exoneration concluded a 2 ½ year review by U.S. attorneys of all D.C. convictions involving hair samples, exposing problems in the FBI lab's methods that have now forced the Department of Justice to conduct a nationwide review of more than 2,100 convictions in 1980s and '90s.

Since 2012, D.C. superior court judges have exonerated two other men— Santae A. Tribble of murder and Kirk L. Odom of rape—after the results of DNA tests overruled evidence presented by FBI hair examiners. The murder conviction of Cleveland Wright, another client of the D.C. public defender's office, has also been vacated and he awaits a judge to declare him innocent.

Collectively, Wright, Tribble and Odom spent almost 80 years in prison.

Sources: www.abajournal.com, New York Times, www.cnn.com, www.mlive.com, news.yahoo.com, Associated Press, www.huffingtonpost.com, myfoxchicago.com, Washington Post, oklahomawatch.com, www.nola.com, Detroit Free Press, www.eji.org, www.opposingviews.comf www.innocenceproject.org, New York Daily News, www.newsobserver.com, www.newson6.com