We are back now with new details about the suspected golden state killer. Joseph Deangelo is now behind bars as questions grow about how investigators tracked him down using his DNA and that genealogy website. ABC's whit Johnson is in Ventura, California, with the latest details. Good morning, whit. Reporter: Robin, good morning to you. We're learning that DNA recovered from a double murder scene here in Ventura played a critical role in cracking the case. Investigators say that DNA was then plugged into the genealogy website that ultimately led to a former police officer Joseph Deangelo. ABC news learning this morning accused golden state killer Joseph Deangelo is on suicide watch, alone in a jail cell after undergoing a psychiatric evaluation. Reported to appear dazed with delayed speech. The 72-year-old entered a Sacramento court Friday handcuffed to a wheelchair. But retired investigator Paul holes who spent more than two decades searching for the killer and is still consulting on the case says it's all an act. He's a dangerous man. He is not the decrepit individual you see in the wheelchair at arraignment but a spry 72-year-old physically capable. He has numerous guns registered to him. Reporter: He says the week before the arrest, Deangelo was seen riding a motorcycle at high speeds and also enjoyed building and flying model airplanes and went to great lengths to make sure his house blended in. He is somebody that is -- he's diligent at putting the effort out to at least maintain a father said, you know, looking like a Normal individual. And I believe that it possibly is part of his act. You know, he wanted to blend into this neighborhood and not be perceived as a monster that possibly was living within this house. Reporter: And this morning the method investigators used to find their suspect is being called into question. Plugging old crime scene DNA of an unknown attacker into the genealogy site ged match and building extensive family tree, a pool of thousands narrowed down to a handful that investigators say ultimately led to the name Joseph Deangelo. There's just the slippery slope of if you can use people's DNA without their consent for law enforcement, it could possibly be overreach by the government. Reporter: Holes says he first pushed the idea. What do you say to critics who argue this is an invasion of privacy, what you did in this case? What it is is it's acting as a witness. Just like when I go up and I knock on a door and I say, hey, did you see somebody who looked like that. He said, yeah, I saw him running down the street that way. That DNA is doing the same thing, but I just don't have to talk to that person. Reporter: Ged match telling ABC news while the database was created for genealogical research it is important that ged match participants understand the possible uses of their DNA including identification of relatives that have committed crimes or were victims of crimes. And the former Auburn police chief telling ABC news investigator Paul holes reached out to him about six weeks ago. The chief explained that Deangelo threatened to kill him after he was fired. Investigators say that information helped narrow their focus on Deangelo and the final days leading to his arrest. Robin. Incredible how it all came together. Whit, thank you very much.