Earlier this year, the jury found Reece guilty of murdering Tiffany Johnston of Oklahoma. Their verdict was to sentence Reece to death. On Thursday, the judge made that official by formally sentencing him.
SEE ALSO: William Reece, accused of Houston-area serial killings, formally sentenced to death in Oklahoma
In 2015, DNA evidence and phone records helped provide instrumental evidence in the case of 19-year-old Tiffany, who was found murdered in 1997. Tiffany's mother, Kathy Dobry, fought for nearly two decades to find her daughter's killer. After Reece was charged in Oklahoma, he started opening up about cases here in Texas.
Reece is accused of killing three other women in Texas back in 1997, including Kelli Cox, Jessica Cain and Laura Smither.
The Friendswood Police Department was instrumental in the Texas cases and bringing them to justice. They led the efforts to find the remains of Kelli and Jessica.
SEE ALSO: Remembering Jessica Cain, 24 years after her disappearance
Now, for the first time, Friendswood police investigators are giving ABC13 an in-depth look into their interactions with Reece as they searched for the young women.
"I don't want to call him clever, but you know, he was definitely calculating. He really kind of thought he was smarter than everybody else," said Chief Robert Wieners with Friendswood Police Department.
The accused serial killer spent five months in the Friendswood City Jail back in 2016.
SEE ALSO: Experts: William Reece fits 'serial killer' profile
At the time, Reece was serving a 60-year sentence in Huntsville for kidnapping, but police brought him down to Friendswood after he told a Texas Ranger he could lead investigators to the body of 20-year-old Kelli - who was a University of North Texas student when she disappeared in 1997.
"We brought Reece out there, you know, had him demonstrate to us how he buried the bodies," said Wieners.
Friendswood police also led the excavation efforts. But when they didn't initially find Kelli's remains, Reece led them to a second site off Orem Drive where he revealed they would find the remains of 17-year-old Jessica, a Tiki Island teen who also vanished in 1997.
"He kept saying, 'I can guarantee you she's right here,' and I said, 'Bill, we've already dug right there.' He kind of cussed and said, 'You're wasting everyone's time out here. I don't know why you're going all the way over there,'" said Josh Rogers, Deputy Chief of Friendswood PD.
It turns out, the layout of the field had changed since he allegedly buried Jessica in 1997. A fence was put up over the years. Once that fence was taken down, they were able to locate Jessica's remains almost immediately.
Then soon after, police located the remains of Kelli in Brazoria County.
Police said Reece confessed in an attempt to avoid the death penalty in Oklahoma after new DNA evidence linked him to the 1997 murder of Tiffany Johnston. He also admitted to killing 12-year-old Laura Smither of Friendswood in 1997.
SEE ALSO: EXCLUSIVE: Ex-wife sheds light on suspected serial killer's past
While Reece was in the Friendswood jail, police said he would draw, even sketched, a drawing of the investigators involved in the case.
"In some strange way, he thought there was a friendship. He wanted to come off as a good guy. Even though in the back of his mind, he probably knew also, that we knew what he did," said Detective Doug Bacon with the Friendswood Police Department.
"You would think he was just an ordinary guy, but obviously, he wasn't. There was a dark side to him.," said Bacon.
The victim's family and their journey for justice
Reece faces execution in Oklahoma, but families in Texas are still pushing for justice for their own daughters.
"I want him found guilty in Texas. I want him sentenced to death in Texas," said Jan Bynum, the mother of Kelli Cox.
Kelli disappeared after she got locked out of her car during a trip to the Denton jail while visiting for a course related to her studies.
When she went missing, she had a one-year-old daughter, Alexis.
"He took her joy of raising Alexis away," said Bynum, "I know a lot of times I find myself going, 'Kelli, you would be so proud of Alexis. You would be so proud of this, or this, or whatever has happened, just she reminds me of you,'" said Bynum.
For years, Kelli's family grieved and searched for answers until 2016, when Reece finally led investigators to her remains in a Brazoria County pasture.
Kelli's daughter, who is now an adult, and also a student at UNT, recalls learning the news about her mother's remains.
"It was awful. It was awful. I remember looking him up and seeing his face and then reading about all these other girls. I just remember reading and thinking about how she must have felt and how scared she had to have been," said Alexis Bynum, Kelli's daughter.
Kelli's family is now in talks with the Brazoria County District Attorney's Office, asking for Reece to face trial in her murder.
"I wasn't there to save her life, but I am here to ensure that there's justice for Kelli," said Jan.
Reece is also accused of the murder of 12-year-old Laura, but has never faced trial in her death. Laura vanished from her Friendswood neighborhood in April 1997 after going for a jog. Her body was found weeks later.
"Reece was the prime suspect in Laura's case. He was interviewed as a known sex offender, but they didn't have anything to link him to Laura," said Gay Smither, Laura Smither's mother.
It wasn't until 2016 that police say Reece admitted to killing Laura.
While her family wants him to be prosecuted, they take comfort in knowing he'll never walk free again.
"The fact that he received the death penalty in Oklahoma, we feel that we got justice for all the girls in that verdict," said Smither. "There was certainly a long period when we felt like that was never going to happen. Now, we know he's not going to get out."
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