MOSCOW, Idaho (NewsNation) — For more than five weeks now, someone has been carrying around the secret that they murdered four people in Moscow, Idaho.

Is it possible that the killer is exhibiting strange new behaviors, giving off telltale signs that would be huge red flags?

On Tuesday, NewsNation’s Ashleigh Banfield asked Robin Dreeke, retired FBI special agent and head of the Counterintelligence Behavioral Analysis Program, what kind of signs the people of Moscow should be on the lookout for.

Dreeke says to stay present and observe “what deviates from someone’s normal behavior.”

“We’ve all experienced this … We can always tell when someone’s having either a really good day or a really bad day, because we pick up a lot of nonverbal cues,” Dreeke told “Banfield.” “The challenge in this situation is more time passes, the likelihood of the personality type starts edging more probably towards psychopathy, and a lack of empathy.”

There are currently two members of the Behavioral Analysis Unit that were assigned from the FBI to this case, and that number has remained the same from the start. Dreeke says this is good news.

“These two are taking in all this information, and they’re basing it off of their expertise in looking at these heinous crimes as a career, and trying to match up the intel that’s coming in with their research on past murders that have been similar,” Dreeke explained.

Dreeke added that these kinds of investigations can go on for while, because the suspect might want “some sort of psychological reward” before turning themselves in.

“If you start edging up towards psychopathy like that, it’s all about grandiosity. It’s how big they can make themselves look … how smarter (they are) than everyone else. It’s a total lack of empathy that they have, which makes it really challenging to see this in a community.”