The disappearance of Jack and Lily Sullivan is suspicious, to say the least. Two children vanish—no solid leads or confirmed sightings since the 1st of May.

Police initially believed that they wandered into the woods and got lost. But after hours and hours of searching yielded no results, it’s becoming clear that this case may be taking a darker turn, with foul play becoming the more obvious theory.

Police have given polygraph tests to a number of people but won’t comment on whether there are any persons of interest in the case—likely because they don’t want to jeopardize the investigation.

A former police detective from Nova Scotia says he believes Jack and Lily’s case is now a criminal investigation. Jim Hoskins, a retired regional police officer and former major crime staff sergeant (who is not working on the case), says the actions taken by police and other agencies involved have led him to that conclusion. He stated that, in his experience, he would be totally surprised if this is not already classified as a criminal investigation.

I think many of us feel the same way. This is a criminal investigation—but authorities may be staying quiet to avoid scaring off potential suspects. In order for charges to stick, they need a solid case.

Police also revealed that they’ve conducted interviews with 54 people and administered polygraph tests to some of them. According to Jim, if they’re giving polygraph tests, it’s because they want to determine whether people’s statements are truthful—as far as the polygraph can interpret.

Hoskins adds that investigators will be working on the balance of probabilities, especially considering that multiple searches of the heavily wooded area around the home have turned up no evidence. If two little kids really wandered into the woods, there would almost certainly be more signs.

The RCMP have stated that their searches of the property where the children disappeared included every aspect of the home grounds—outbuildings, nearby septic systems, wells, mine shafts, and culverts.

“If this is not a criminal investigation now, I’d be totally surprised,” Hoskins says.

It’s been almost six weeks since Lily and Jack Sullivan were first reported missing from their home in Lanstown Station. On Wednesday, the RCMP in Nova Scotia confirmed that multiple RCMP units—including Major Crime—are involved in the investigation, along with the National Centre for Missing Persons.

Police say they have formally interviewed 54 people. And this former Halifax Regional Police officer doesn’t take that lightly:

“They’re out there. And the only way they’re going to see or get results in this is to be out there—talking to people, looking at videos, looking at topography and what have you. They’re not sitting in offices doing this by laptop, let’s put it that way.”

In an update this week, the RCMP said they’ve collected hundreds of hours of video from areas surrounding Lanstown Station between April 28th and May 2nd—the critical window when the kids went missing. They have also received nearly 500 tips from the public.

Police say they’ve searched every aspect of the family’s home and received authorization to seize and examine digital devices.

As Hoskins explains: “They’ll go on the balance of probabilities. Based on the area we fully searched—with a lot of people—we can’t find any evidence: not a backpack, not a shoe, nothing. If we can’t find the kids, then someone has to say, ‘enough is enough’ for searching those areas. Now we move to the only other option—a nefarious one. In other words: a criminal act. That’s only my personal opinion.”

Police also say they’ve used polygraph tests during some interviews. A former polygraph examiner south of the border explains that the test is used to monitor how a person’s nervous system responds to specific questions.

“If somebody is successful in the test, that doesn’t mean they’re eliminated—but investigators will spend more time on those who are not successful. Not passing the test doesn’t mean you’re guilty or involved—it simply means there’s some issue there, maybe some guilty knowledge.”

He also adds that he’s seen people pass tests who were later proven guilty.

More than 160 search and rescue volunteers have scoured the dense woods surrounding the children’s home, but so far, the only physical clue found is a small bootprint.

Still, police continue to refer to the case as a “missing persons investigation.”

But make no mistake: they’re covering it all—every angle, every lead—and you only go that deep when there’s a criminal investigation. With Major Crime on the scene, they’re not there just because of their title. They’re there to do their major crime work.