There is an epidemic of cops killing pets. It is no surprise, really, as it is a direct consequence of the lowering down of standards for law enforcement applicants, which necessarily results in an unprofessional police force, whose staff includes undisciplined cretins and border-line psychopaths as a complement to the officers who truly are disciplined, and dedicated, and professional. There was a time when these low-life scoundrels would have been unceremoniously booted from the force, but policitcal correctness and diversity and the police unions have made that almost impossible today.
Actually, I think this is taught at the Academy Level for Law Enforcement - “When in the slightest doubt about a dog’s intentions - shoot it. There is no penalty if you are wrong.”