My gut feeling is that someone with some power or money pressured the AG to drop this case.
Story from AP (posted on local CBS site):
Montana AG Drops Jail Investigation
MATTHEW BROWN, Associated Press Writer
BILLINGS, Mont. (AP) ― Montana Attorney General Steve Bullock has dropped his investigation into a California company following its attempted takeover of an empty Montana jail.
The company, American Police Force, had missed a Monday deadline to provide documents sought by Bullock’s office after revelations that company founder Michael Hilton had a lengthy criminal background.
But because American Police Force has pulled out of its bid to take over the 464-bed jail in rural Hardin, Bullock said Tuesday he was ending the investigation.