He’s a Sergeant and doesn’t know you can’t arrest someone for a crime they are “suspected” of committing the day before. He’d need a statement, police report and evidence to get an approved warrant first.
Secondly, if he doesn't know the difference between a tazer ahs a gun, which are on different sides of his body and are different colors, he shouldn't have access to them.
Thirdly, he shot an unarmed teen, who was NOT a threat, that was running AWAY from him, back turned, in the hip, means he's a coward and a potential murderous terrorist so he shouldn't be a poliice...