Policemen and lawmakers and attorneys in dreams and visions speak of people who make and monitor laws and the conduct of people. Investigators speak specifically about the investigation of such conduct to gain more knowledge. They check if the conduct is legal or not. In a negative sense, legal officers may speak of legalism. In a positive sense, it speaks of making sure that things are carried out as they should. A summons or a warrant of arrest or similar legal documents speaks of such people being lawfully empowered to act on behalf of the government or an authority who appointed them.
The presence of a warrant of arrest may indicate that someone is indeed guilty of wrongful conduct.