I believe you are thinking of the term “assault weapon”, which was a term invented to help ban semi-automatic military-style rifles, that arguably aren’t signif

I believe you are thinking of the term “assault weapon”, which was a term invented to help ban semi-automatic military-style rifles, that arguably aren’t significantly deadlier than other less scary looking semi-automatic rifles, but are politically more convenient to ban. “Assault rifle” is a valid term but it only refers to automatic rifles, which were already effectively banned for civilians. I don’t know whether that rifle (carried by a police officer) is automatic or semi-automatic.