The Police Policy Studies Council? Who funds them, the Police Unions? Not sure that I would trust them to have unbiased research. It certainly conflicts with Federal Bureau of Labor Statistics data.
Police Detectives make the list (after truck drivers, cashiers, construction workers and many others). The main hazard of being a detective? Car crashes, same as truck drivers. Firefighters don’t even make the list. Apparently Barbeque at the station, runs at the park, and very occasionally running into a burning building is not so dangerous as many believe.