The purpose of this study is to examine the usefulness and importance of certain characteristics involved with firearms transactions and regulations as related to illicit firearms markets nationally, and in the State of California. Data from requests to the Bureau of Alcohol, Tobacco, and Firearms by local law enforcement agencies for tracing the origin of firearms were analyzed for the years 2003-2006 along with purchase and other available information in effort to explain time-to-crime, the time from original purchase of the weapon to when it was recovered by law enforcement and submitted for tracing. Requests for tracing were analyzed for categories of state-level regulation and characteristics of legal context, dealer characteristics, purchaser characteristics, purchaser-possessor relationship, and characteristics of possessor-gun (age category and pistol). Results suggest that regulations regarding purchase and registration of firearms may serve to assist law enforcement in limiting the diffusion of illicit firearms to some extent. Time-to-crime (a reported indicator of illicit firearms activity) varied depending upon the extent of regulation within states. Certain characteristics associated with illicit firearms also appear to mediate the relationship of statutory context and short time-to-crime firearms. These analyses are repeated for California as a unique jurisdiction providing data from secondary purchases from sources such as individuals, gun shows and flea markets. Conclusions are presented to suggest that more regulation will reduce the availability and distribution of illicit firearms.