The purpose of this qualitative, descriptive multiple case study was to explore what process, policies and procedures, or set of empirically supported norms governed law enforcement officers in a selected county in the southwest region of the United States when threat assessments were conducted on potentially violent subjects threatening mass homicide or harm. Research had been done exploring threat assessments and the evaluation of violence potential through such foundational theories as the pathway to violence, the concept of leakage, and typologies of warning behavior indicators of violence; however, there was a gap as to what process specifically law enforcement officers used to evaluate violence potential via threat assessments. Three research questions for this study were: (a) what processes were law enforcement officers in a selected county in the southwest region of the United States using when threat assessments were performed to determine violence potential of subjects threatening to commit mass homicide or harm; (b) what policies and procedures guided the threat assessment processes; (c) were the processes aligned with an empirically approved threat assessment process. A total of 10 cases were evaluated via observation and interview. Major process themes were covered in pattern matching logic, replication design, as well as cross-case synthesis evaluation to determine that law enforcement officers were utilizing a clear process for the threat assessments, and the processes aligned with an empirically approved guideline. There were no existing policies and procedures, but this research showed that the same process was ultimately being utilized across multiple jurisdictions in the area researched. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]