Texas woman Darlie Routier has sat on death row for two decades now, ever since her 1997 conviction for the murder of one of her two slain children. Some think the case is open-and-shut, but others believe Routier has been framed for the grisly deaths of sons Devon, 6, and Damon, 5. Now, a new TV show called The Last Defense, executive produced by Viola Davis, will reinvestigate the events of June 6, 1996, in Rowlett, TX.

At 2 a.m. local time that night, Routier called 911, yelling, "They just stabbed me and my children." When first responders showed up to her house, they found the then-26-year-old wife and mother holding a towel to a stab wound on her neck. They also found Devon dead and Damon dying, both boys having sustained deep stab wounds to the chest. Routier told the cops she had woken up to find a man on top of her, but soon they grew suspicious.

"There were these inconsistencies with her story and physical evidence," Lt. David Nabors, head of the Rowlett Police Department's Criminal Investigations Division, told the Rowlett Lakeshore Times in 2016. "You collect the physical evidence and it's either going to prove or disprove her story."

For one, the bread knife used to cut an opening in the patio screen and the butcher knife used in the stabbings both came from the knife block in the kitchen, Nabors explained. "If the bread knife was used to cut the screen, somebody had to come in, get the bread knife, cut the screen, put it back in the knife block, and then get another knife to commit the murders," he said.

https://www.youtube.com/watch?v=mVo67CeG82E

Additionally, the blood evidence — including Damon's and Devon's blood on her shirt — suggested she was holding the knife and she wasn't cut on the couch. "She's laying on the couch and gets her throat cut, [but] there's no cast-off on the couch where she said she was cut," Nabors said. "None, not even blood drops."

Routier claimed she chased her attacker out of the house, but the blood stains on the floor were passive, not indicative of any fast action like running or chasing. Instead, Nabors said, the blood drops showed Routier was walking through the scene. Additionally, investigators found the kitchen sink was used in a cleanup, with traces of blood in and around the sink.

Finally, Routier was a light sleeper, according to her husband, Darin — and that fact seemingly contradicts her version of events. "One of the problems we had was, one of the children was at the foot of the couch where she was sleeping," Nabors said. "The other one was perpendicular to that within three feet of her, but somebody came in the house stabbed both children and then attacked her but she slept through it. That was another inconsistency in her story."

The investigators pursued multiple leads but eventually concluded it was an inside job, pegging Routier as the prime suspect. "The evidence kept pointing back to someone in the house," Nabors said. "The evidence kept pointing back to her and her inconsistencies in her statements."

According to Nabors, Routier showed no emotion in the two weeks before her arrest. But she cried when she was arrested. She was charged and convicted of capital murder for the death of Damon, and she was sentenced to death by lethal injection.

"It's very tragic, a five- and six-year-old murdered and their mom was convicted of it," Nabors said. "It definitely hits a nerve with people. Some don't want to believe that a mother is capable of doing that."

Meanwhile, as Rolling Stone reports, Routier's supporters claim the police staged the crime scene and prosecutors misconstrued her frame of mind. Additionally, in 2002, a forensic anthropologist found a bloody fingerprint found on a glass table didn't match anyone in the Routier family or anyone involved in the investigation.

These days, as she awaits further DNA testing as part of her appeal, Routier is still on death row in Gatesville, TX. Her mother, Darlie Kee, says Routier is still positive and sure the truth will come out: "She's innocent and that's all that matters."

But the Roulette Police Department is "totally comfortable with the sentence and the trial," Nabors said. He added, "If it wasn't a solid case she wouldn't be sitting where she's at."

Now the case is getting another examination in The Last Defense, along with the case of Julius Jones, another convicted murderer who maintains his innocence. "The seven-episode docu-series explores and exposes flaws in the American justice system through emotional, in-depth examinations of the death row cases of Darlie Routier and Julius Jones," ABC says in a press release. "The series will seek to trace the path that led both Routier and Jones to their places on death row while taking a deep look into their personal stories … [After] 20 years on death row in Texas, the contentious debate over the fairness of [Routier's] trial is more polarized than ever."

The Last Defense premieres on Tuesday, June 12, at 10 p.m. ET on ABC.