List four reasons why police discretion is necessary, as indicated by Sheehan and Cordner (1989).

•   A police officer who attempts to enforce all the laws all the time would be in the police station and in court all the time and thus of little use when serious problems arise in the community.
•   Legislatures pass some laws that they clearly do not intend to have strictly enforced all the time.
•   Legislatures pass some laws that are vague, making it necessary for the police to interpret them and decide when to apply them.
•   Most law violations are minor in nature, such as driving slightly over the posted speed limit, and do not require full enforcement of the law.
•   Full enforcement of all the laws all the time would alienate the public and undermine support for the police.
•   Full enforcement of all the laws all the time would overwhelm the criminal justice system, including the prisons.
•   The police have many duties to perform with limited resources; good judgment must therefore be used in establishing enforcement priorities.