How about the fact all those people are already criminals?
How about illegal immigrants are more likely to target other immigrants and go unpunished?
How do they even know how many illegal immigrants there are in the US, what number they're feeding into?
""" “There’s lots of opportunity to commit crimes in Mexico and Venezuela and other places people are emigrating from,” Light says. “The argument is that many people who want to immigrate are selected on attributes like ambition to achieve, to find economic opportunities, and those types of things aren’t very highly correlated with having a criminal propensity.” """
They are drawing conclusions while I think their findings are highly questionable. It's ultimately just an opinion piece.