In the videos recorded during two days in August inside the Frederick Police Department in Colorado, Chris Watts admits to detectives that his marriage was in trouble, he was having an affair and says he told his wife the morning she disappeared that he was leaving her.
Watts' wife, Shannan, was raised in Aberdeen. The couple met in North Carolina before moving to Colorado to raise their daughters, 4-year old Bella and 3-year old Celeste.
"Obviously it's getting pretty emotional," Watts told detectives, describing the early morning conversation with his wife. "We're talking about we felt the disconnection was there. We're falling out of love."
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The lead detective expressed skepticism about the story:
"The day (Shannan) goes missing is the day you guys have marital discord," he said. "You can understand what I'm thinking about you."
At that point in the interview, Watts maintained his innocence.
"It honestly just makes me sick to my stomach because this is something that I would never do," Watts said. "There's no way I would harm anybody in my family at all. I am telling you the absolute truth."
But one day later, Watts' story changed after detectives told him that he failed a lie detector test.
"It is completely clear that you were not honest during the testing," a detective told Watts. "And I think you already know that. You did not pass the polygraph test."
Police then brought in Watts' father to the interrogation room. That is when Watts admits for the first time to anyone that he killed his wife.
Warning: Video contains explicit language
"They were, they were blue," Watts told his father.
"She choked both of them to death?" Watts' father asked.
"I freaked out and did the same (expletive) thing to her," Watts said.
When detectives returned, Chris Watts' version of the truth was that Shannan killed their daughters and when he discovered what she did, he killed Shannan in a rage.
Warning: Video contains explicit language
"The evil that I saw when I walked behind Shannan when she was behind (Celeste)," he said. "I didn't know what to do. I didn't know what to (expletive) do. None of this made sense!"
Watts holds steady to his denial of killing his own children.
"I'm not that person. She hurt my kids," Watts said in an attempt to explain why he killed his wife.
Investigators press him on why he didn't call 911. They say loving parents struggle to accept that their child has died. So even if they're blue and unresponsive, they call 911 and hold out hope that they can be revived.
Investigators tell Watts they are left with only one option: that Watts is a monster.
"I'm not that monster I didn't kill my babies," Watts said.
That turned out to be a lie.
Watts ultimately admitted in court that he killed Shannan and his daughters then dumped their bodies in a Colorado oil field.
Watts eventually showed the detectives where he hit the bodies using a map in the interrogation room. However, he tells investigators he does not want to take them to the location or have any of his coworkers who know the area help them, because they "think I'm a good man."
Watts will spend the rest of his life in prison -- after he pleaded guilty earlier this month.
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