Law enforcement officials are getting frustrated in their search for a coherent motive that might help explain why 64-year-old gambler Stephen Paddock opened fire on 20,000 concert attendees in Las Vegas, and the lack of an explanation is causing many Americans to wonder if ISIS’s claims of responsibility should not be taken more seriously. ISIS has claimed that Paddock was one of their own, having converted to Islam six months before the shooting, but they have yet to provide any evidence that he was in contact with the overseas terrorist organization. And so far, the FBI and Las Vegas police say they have uncovered no information that would lead them to believe there is a link.

However, as a leading terrorist expert told Newsweek, there could be a very good reason why the Islamic State has kept mum on any corroborating evidence for their claim.

“If Islamic State did indeed cultivate Paddock, as it has claimed was the case, the group surely has some evidence of its engagements with him. If it does, it may be the case the group is waiting on FBI and other agencies to dismiss its claim of responsibility for the Las Vegas attack before posting contradictory evidence online for the world to see,” expert Michael S. Smith II told the magazine. “Islamic State has been very focused on undermining confidence among civilians in the West that their technologically-superior governments are competent managers of our collective security.”

If there’s a fault in this analysis, it’s that law enforcement agencies have already dismissed the connection, so if ISIS wanted to undermine American trust in the FBI, they could have come out with the correspondence already. Maybe they’re waiting for the agencies to make a more definitive denial? Or, perhaps, there really is no connection between ISIS and the shooter, and this is all just a sick publicity game being played by the jihadists.

It’s not a stretch to attribute that sort of mind game to the terrorists. The only problem is that ISIS does not, habitually, make claims they can’t back up. Yes, they have taken credit for attacks they had nothing to do with – the botched robbery in the Philippines being the most prominent example – but it’s not part of their regular M.O. More often than not, when they claim credit for an attack, the killer was at least highly influenced by the group, if not materially supported by the terrorists. For them to make this claim three times, in increasingly specific levels of detail, makes us wonder if investigators are telling us the whole truth.

Which, if Smith is right in his analysis, is exactly the objective ISIS is hoping to achieve…