Militarization of police
People have noticed that the way police handle protests is becoming more like the military. Since the 1970s, police who control riots have been shooting at protesters with rubber or plastic bullets. They also use tear gas, which was first made by the US army in 1919 to control riots. Using tear gas in wars is not allowed by international agreements that most countries have signed, but using it in a domestic (inside of a country) situation or non-combat situation is allowed by police or the military.