The United Nations Code of Conduct for Law Enforcement Officials states that "law enforcement officials shall respect and protect human dignity and maintain and uphold the human rights of all persons" (Article 2) and they "may use force only when strictly necessary and to the extent required for the performance of their duty".
The Basic Principles on the Use of Force and Firearms by Law Enforcement Officials also include the following:
4. Law enforcement officials, in carrying out their duty, shall, as far as possible, apply nonviolent means before resorting to the use of force and firearms.
5. Whenever the lawful use of force and firearms is unavoidable, law enforcement officials shall:
(a)Exercise restraint in such use and act in proportion to the seriousness of the offence and the legitimate objective to be achieved;
7. Governments shall ensure that arbitrary or abusive use of force and firearms by law enforcement officials is punished as a criminal offence under their law.