Sean Mannix

Retired Cedar Park Police Chief

Sean Mannix is a distinguished law enforcement professional with 36 years in public safety. Throughout his career, he has held significant leadership roles, including serving as the Assistant Chief of Police in Austin and as the Chief of Police in Cedar Park, Texas. His focus has constantly been refining policing methods, integrating advanced training, and fostering strong community leadership. After retiring in 2020, he contributed to public service as the Statewide Traffic Incident Management Coordinator for the Texas Department of Transportation.

Childhood and Family

Sean was born in California and grew up as one of five children. From an early age, he felt a strong calling to law enforcement, influenced by his father, a dedicated law enforcement officer. At 18, he enlisted in the U.S. Marine Corps Reserve, an experience that would help shape his leadership abilities and instill a robust work ethic that would guide him throughout his career.

Educational Background

He graduated with honors from Excelsior College with a Bachelor of Science in Criminal Justice and a Master of Arts in Homeland Security from American Military University. His academic credentials were further bolstered by his participation in elite leadership programs, such as the FBI National Academy, the Leadership Command College, and the Senior Management Institute for Police. Additionally, he completed the LAPD West Point Leadership Program, enhancing his expertise in law enforcement leadership.

Starting His Law Enforcement Career

Joining the Alameda Police Department

After completing his service in the Marine Corps, Sean returned to Alameda, California, to embark on his law enforcement career. At just 20 years old, he became the youngest officer at the Alameda Police Department. In the early years of his career, he gained invaluable experience in various patrol duties and emergency response, which laid the foundation for his future success in law enforcement.

Moving to the Austin Police Department

In 1993, Sean moved to Austin, Texas, to continue his law enforcement journey with the Austin Police Department. Over the next two decades, he worked his way up the ranks, starting as a patrol officer and advancing to positions of greater responsibility. His work included overseeing critical divisions, such as the Organized Crime Division, and tackling large-scale criminal activities. His leadership in the Central Bureau, which focused on crime prevention and community safety, shaped the department’s success.

During his time in Austin, Sean implemented effective strategies, such as the COMPSTAT model, to reduce crime, enhanced community outreach programs, and strengthened partnerships with federal agencies like the FBI and DEA, which marked significant achievements in the department’s growth and effectiveness.

Becoming Chief of Police

In 2013, Sean took on the role of Chief of Police for the Cedar Park Police Department. He quickly worked to improve the department's training programs, emphasizing community policing as a key strategy. Community policing, which fosters positive relationships between officers and the people they serve, was a cornerstone of his leadership philosophy.

During his tenure, Sean introduced several innovative initiatives, including de-escalation training, the implementation of body-worn cameras, and a wellness program for officers that gained national recognition. Under his guidance, the department became a highly respected workplace with a diverse and committed staff and a strong sense of community trust.

Recognition Across the Nation

Under Sean Mannix’s leadership, the Cedar Park Police Department earned dual accreditation from the Texas Police Chiefs Association and the Commission on Accreditation for Law Enforcement Agencies (CALEA). He also helped the department excel in National Night Out participation, a nationwide event designed to build stronger relationships between police and the communities they serve. Cedar Park consistently ranked among the top in Texas for its involvement in National Night Out, reflecting the effectiveness of its community engagement efforts.

Retirement and Life After Law Enforcement

In 2020, he retired as Chief of Police in Cedar Park after more than 30 years of service. Though his active law enforcement career ended, he remained engaged in public service, continuing to work in roles that supported first responders. He serves as a board member for Sigma Tactical Wellness, an organization that promotes the health and wellness of first responders, focusing on cardiac and overall wellness. He is also a supporter of Williamson County Crime Stoppers, a nonprofit organization dedicated to solving crimes and improving public safety.

Beyond the Spotlight

Outside of his professional life, he is a devoted husband and father. He has been married to Eileen for many years, and they have four daughters. In September 2025, they will celebrate their 20th wedding anniversary, marking two decades of mutual love and support.

Sean enjoys outdoor activities such as fishing and aviation in his free time, which provide him with a much-needed respite after years of service in high-stress roles. He is also an avid reader, constantly learning and expanding his knowledge, whether related to law enforcement or a good novel. For him, lifelong learning is key to staying sharp and engaged professionally and personally.

Through his extensive career, Sean Mannix has shown unwavering commitment to public safety, leadership, and community service, impacting law enforcement and the lives of those he served.