Relative ethics is complicated and have multitudes of sides with varying shades of gray.
Absolute is just being one or the other. Unethical behavior like bribery, extortion, excessive force and perjury are all unacceptable behavior police. In Relative Ethics the community can start to accept wrong behavior like looking away while police officers deal in drug trafficking.This is an example officer improper and illegal behavior. Another example maybe letting go a serious offender just to use him as an informative later. This is end justifying the means.
Managers and supervisors must maintain cultural integrity by finding great officers during the interview process.