Ron Zimmerman, Director

Prior to becoming the Director of ImmCon, Ron Zimmerman worked for over 28 years as an Immigration and ICE Special Agent. He began his career in uniform as a U.S. Border Patrol Agent before being promoted to a Criminal Investigator in October 1987 to work in the then new Employer Sanctions Program (known today as the Worksite Enforcement Branch of ICE Investigations.)

Throughout his career, Mr. Zimmerman handled all aspects of Immigration Enforcement to include both Administrative and Criminal Law. Working his way through the ranks to Special Agent, Supervisory Special Agent, Officer In Charge and Group Supervisor, Ron retired/finished his career in 2011 in charge of the Worksite Enforcement Branch in the Southern District of California, overseeing the entire program for both San Diego and Imperial Counties.

Robert Butler, Team Lead

Robert Butler has 29 years of INS experience, with nine years of overseas experience as the INS Officer in Charge at the American Embassies in Seoul, Korea and Tokyo, Japan. His initial involvement with the INS Employer Sanctions Program began when he was assigned to the Western Region Investigations staff in 1987. Immediately following the passage of IRCA, he was given the responsibility of developing the Employer Sanctions Program at the Regional level. He planned and hosted training seminars for INS District Employer Sanctions managers and supervisors. During his Regional tenure, he was also assigned the oversight of the Immigration Status Verification (SAVE) Program.

Since retiring from INS, he has been involved in the worksite-related business as a Senior Managing Compliance Consultant. As such, he has assisted in the development of the electronic I-9 form and automated auditing program. As part of his consultant activities, he has also conducted thousands of Form I-9 compliance audits.

Ralph Kastner, Team Lead

Ralph Kastner has over 26 years of experience as an INS and ICE Special Agent, with 13 years as a Supervisory Special Agent. He began his career as a Border Patrol Agent and was quickly promoted to a Criminal Investigator and subsequently to a Special Agent assigned to the Imperial County, Calexico, CA Office.

He was introduced to the employer sanctions provisions of IRCA while assigned to the Employer and Labor Relation division in 1988. While in Calexico, he conducted and supervised criminal and administrative immigration investigations for the Worksite Enforcement Branch with a heavy emphasis on farming and manufacturing businesses. He is an expert on the I-9 form and the many nuances associated with the proper hiring practices needed to maintain a migrant work force. Additionally, Mr. Kastner is fluent in the Spanish language.

Don Evans, Team Lead

Don Evans has over 30 years of experience with the U.S. Government. First as a Border Patrol Agent, then as an Immigration Special Agent, and finally as an ICE Special Agent. Throughout the majority of his career Don has been assigned to the Worksite Enforcement Branch and conducted numerous investigations of companies and audits of their I-9 Forms.

For the past seven years, Don worked as the ICE Computer Forensics Examiner, which included the examination of electronic I-9 systems to ensure that they met each of the government's requirements.

Don is an expert on procedures, policies and tactics used by Special Agents to investigate companies. He knows exactly what the government requires of an Electronic I-9 and how they examine your computer systems to ensure compliance.


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