Investigative experts say the behavior of Colorado dad Chris Watts before his arrest in the deaths of wife Shanann and their daughters was not unusual
chris watts
Credit: Weld County Sheriff's Office

For many, it was the most startling twist in a case full of mysteries: A day before he was accused of their murders, Colorado dad Chris Watts stood outside his home and pleaded for the safe returns of his wife and two young daughters, who had seemingly vanished a day earlier.

However, investigative experts tell PEOPLE, Watts’ behavior comes as no surprise.

“He has an incredibly large ego,” says Dale Yeager, a criminal analyst and forensic profiler who is unconnected with the case, adding, “He really comes off as sociopathic. That doesn’t mean he is mentally ill, just that he has a personality defect.”

Drawing a parallel between Watts’ case and that of Scott Peterson, who notoriously murdered his pregnant wife and then repeatedly gave interviews, Yeager says, “He’s Scott Peterson, just less charismatic.”

Speaking to local TV station KMGH outside his home in Frederick on Tuesday, the 33-year-old Watts said of wife Shanann Watts and girls Bella and Celeste:

“If somebody has her and they’re not safe, I want them back now.”

“That’s what is in my head. If they’re safe right now, they’re going to come back,” Chris said. “But if they’re not safe right now, that’s the not-knowing part. Last night I had every light in the house on, I was hoping that I would just get ran over by the kids just running in and barrel-rushing me, but it didn’t happen. And it was just a traumatic night trying to be here.”

Shanann’s body was found Thursday on the property of an oil company where Chris had worked. Authorities believe the remains of their daughters were found later that same day, not far away.

Chris remains in jail, scheduled to return to court next week to be formally charged, and his attorney did not respond to PEOPLE’s request for comment.

RELATED VIDEO: Pregnant Mom & 2 Daughters Likely Killed at Home — Allegedly by Husband — Before Bodies Were Dumped

chris watts
Chris Watts
| Credit: Weld County Sheriff's Office

In the opinion of criminologist Philip Stinson, who like Yeagar is unconnected to the case but who analyzed footage from Chris’ interviews, the incongruity of him speaking to reporters likely has a simple explanation.

“He just played the role of the devastated husband, concerned for his wife and his two daughters,” Stinson explains.

However, he says, that may have come at a cost:

“[Chris] was acting the way he thought he should be perceived and the police were playing very close attention. I think when he started talking to the media, the authorities at that point would have been paying very close attention to what he was saying, in context to what he may have said to them.”

• Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter.

In court on Thursday, prosecutors said — without elaborating — that they believe Shanann was killed along with their daughters in their house.

The trio was reported missing Monday afternoon about 12 hours after Shanann returned from a business trip in Arizona.

Shanann, who was 15 weeks pregnant, had been preparing for a sex reveal party scheduled for this Saturday, according to a friend.

Her brother has previously said she was going to give birth to a boy to be named Niko.

From left: Chris and Shanann Watts

Yeager, the profiler, says he thinks Chris likely believed he would be able to get away with his alleged crimes, given his inflated ego.

“His ability to lie is very clear,” Yeager believes. “He is a manipulator and manipulators, their ego is so high, they see the people that are holding them back as objects they can dispose of. From that interview, you can tell he has convinced himself this is good for him and it’s very Machiavellian in that regard.”

Both Stinson and Yeager suspect financial and marital woes may have played some part in the murders but noted that was merely speculation based on years of analyzing similar crimes.

Authorities have not disclosed either causes of death for Shanann and her daughters or a motive in their slayings.

However, a family friend previously told PEOPLE she and Chris “were having marital problems.”

Scott Peterson (right) with his late wife, Laci Peterson
| Credit: ZUMA Press

Stinson, a Bowling Green State University professor, believes the killings likely were not planned.

“I think maybe he became enraged,” he says. “I would be surprised to learn he was laying in wait and that these deaths were calculated — that there was a whole weekend of preparation.”

What’s more, in Stinson’s professional opinion, police were probably looking at Chris before the interview — and then him talking to reporters only aided their work.

“I saw that interview and I got that gut feeling that this guy is hiding something. He is guilty as sin,” Stinson says. “All of those things about his demeanor — his body language, his expressions, his words — are all things, I would guess, that immediately got the attention of investigators who recognized this stuff just isn’t adding up.”