Online crime maps, which plot law enforcement crime data, promise to promote civic engagement and increase government transparency. This study reviewed the websites of the 250 largest U.S. cities and found 65% host or link to a crime map, and that 116 police departments entered into agreements with crime mapping companies that provide the companies preferred or exclusive access to local crime data, curtailing public access and use. This study examines the legal tactics used by commercial mapping companies to maintain information control, explores recent examples of legal battles over the data, and proposes solutions, including targeted public record law amendments, parallel access, and a generalized right of access.