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Richard Ferrell

President/CEO/Program Developer and Instructor

  • 18 Year Law Enforcement Officer

  • 10 Years as an Active Shooter Survival and Response Instructor

  • 10 Years as a law enforcement firearms instructor 

  • 10 Years as a FEMA CERT instructor

  • 8 Years as a disaster management coordinator

  • 8 Years as a FEMA ICS instructor

Welcome! I am Richard Ferrell, CEO and President of Sentry, Inc. Our company specializes in safety and security training, investigations and physical security patrol services. Recently, I retired from the police force with over 18 years of experience in patrol and as a valued member of our officer and civilian training unit. 


I wanted to continue serving my community post retirement by utilizing my skills and experience to make positive and impactful cultural changes to society and institutions to improve safety and security.

I am passionate and excited about solving problems that impact the largest number of people possible and continue to have long lasting effects that are cost effective.

One of the most enjoyable assignments I had as a law enforcement officer was to provide instruction for active shooter survival and response, disaster management, and firearms. I enjoy teaching and it shows when I interact with a class. With over 10 years as an adult educator, my experience has allowed me to develop interesting, effective and valuable material for instruction. I believe in engaging and exciting classes that involve a combination of lecture, group activities and hands on exercises. The content I provide in my instruction is unique, comprehensive and relative. I have trained thousands of students and managed a disaster management program for many years.

I spent a significant time in patrol where I learned valuable techniques in effective patrol operations that focus on crime prevention and community relations. While a police officer, I was an active member of outreach programs and systems to address community needs through innovative problem solving. these skill translate into progressive and result driven security operations.

I look forward to assisting businesses and institutions that desire to change the culture of safety and security.

-Richard Ferrell

Marc A. Garza

Vice President of Investigations

  • 22 Year Law Enforcement Officer

  • 16 Years as a law enforcement firearms instructor 

  • 10 Years as a S.W.A.T. Operator

  • 10 Years as an Active Shooter Survival and Response Instructor

  • 3 Years as a Patrol Sergeant

  • State Licensed Private Investigator

Marc A. Garza is the Vice President of Investigations and the Qualified Manager at Sentry, Inc. He specializes in Civil and Legal Investigations; and Security Consulting.


He is a retired police sergeant with over 20 years of service in San Diego, where he held various assignments in patrol, investigations, firearms training and field training. As a police supervisor, he managed numerous police personnel and supervised the field training program.


During his tenure as a police trainer, he was selected by CAL-EMA to train law enforcement personnel and civilians in Active Shooter (AS) response and mitigation through-out the State of California.


He  has over 1200 hours of specialized training from the California Peace Officer’s Standards and Training Association (CA POST).  


His main goal is to provide focused, credible and actionable investigations for clients that retain Sentry, Inc. for their investigative needs.