Shepard's Citations is a citator used in United States legal research that provides a list of all the authorities citing a particular case, statute, or other legal authority.[1] The verb Shepardizing (sometimes written lower-case) refers to the process of consulting Shepard's to see if a case has been overturned, reaffirmed, questioned, or cited by later cases.[1] Prior to the development of electronic citators like Westlaw's KeyCite during the 1990s, Shepard's was the only legal citation service that attempted to provide comprehensive coverage of U.S. law.[1]