Library of Congress Subject Headings is an alternative to keyword searching. They can narrow down your search much more effectively than keywords.
You can start searching the JFL Catalog in the search box above. Select JFL Catalog from the drop-down menu of searches.
Here are some good Political Science subject headings to use in your searches
Political Science
Political Theory
Government
Conservatism
Liberalism
Here are some good Criminal Justice subject headings to use in your searches:
Arrest
Ballistics
Crime
Criminal investigation
Criminology
Forensic Science
Police
Police corruption
Trials
Victims of crimes
Warrants (Law)