They sound a bit like Iain M. Banks' "slap drones", flying robots tasked with following around known criminals and preventing them from reoffending.

This proposal seems awfully dystopian, but US schools apparently conduct surprise active shooter drills with simulated gunshots, so it feels like a choice between evils at this point.

Proper ethical oversight would needed though, and I'm worried that mission creep is inevitable (remember e.g. tasers themselves were originally intended as "less lethal" and an alternative to a firearm, but are now used routinely to simply get compliance.)