> he can't just not do his job

Yes he can.

No one put a gun to his head and forced him to be a police officer.

There are plenty of jobs that don't involve putting humans into a cage under the threat of death for possessing a plant.

He made a decision to become a police officer and enforce these inhumane laws.

It's like signing up to be a slave catcher then saying "I'm just doing my job" when you return runaway slaves.