Meet Our Team
Sergeant Ken Casaday, Police Officer
Sergeant Ken Casaday obtained his bachelor's degree from Sam Houston State University. Ken also proudly served in the United States Army for five years before eventually settling in Austin, Texas.
Sergeant Casaday brings over 30 years of law enforcement experience to LTISD, including 24 years at the Austin Police Department. While serving at APD, Ken worked on patrol for several years in South and Central East Austin. During that time, he trained and worked as a mental health officer. Ken also served in APD’s elite Metro Tactical Unit and as a detective in the Organized Crime Division. Ken spent his last 8 years at APD serving as the President of the Austin Police Association. Ken is excited about serving the students, teachers, and staff members of the LTISD.
Ken is married to his wife, Jessica, who is a pharmacist and math & science tutor in the Lake Travis area. They are the proud parents of one daughter who is currently in nursing school at Texas State University. Ken and Jessica are also the proud parents of Otis the English Bulldog. When Ken’s not working, he enjoys the outdoors, hunting, fishing, and watching University of Texas Longhorn sports.
Sergeant Donnie Williamson, Police Officer
Sergeant Donnie Williamson brings over nearly 36 years of law enforcement experience to the department, including 27 years at the Austin Police Department (APD). Donnie worked in APD’s Organized Crime Division as well as the Mounted Horse Patrol Unit prior to serving his last 12 years working full-time in the Department’s Mental Health Unit and Crisis Intervention Team.
Sergeant Williamson is married and has three children. When he’s not working he enjoys building race cars and hot rods, and he has a passion for horses.
Steve Adams, Police Officer
Officer Steven Adams has over 33 years of Law Enforcement experience. He started his career in the Bastrop County Sheriff’s Department in 1989. More recently, he served locally patrolling the Village of the Hills while working for the Precinct 2 Travis County Constable’s Office. In 2005 he was recruited to work for Lakeway Police Department, where his most recent duty was as a motorcycle officer in the Special Operations Division.
Adams is certified as a Master Peace Officer, TCOLE Instructor, firearms instructor, field training officer, and mental health officer. His love of the local community and people is commonly given as the reason for his dedication and long service to the Lake Travis area. He believes that the solution to problem solving is a community-based approach involving communication and teamwork between the police and citizens.
When not at work, Steve enjoys reading, motorcycles, and passing time with his wife Beth, son Joshua, and two dogs (Biscuit and Mariah). He is excited to continue serving this community in his new role with the Lake Travis ISD Police Department.
Louis Candoli, Police Officer
Officer Louis Candoli brings over 28 years of law enforcement experience to Lake Travis ISD and has his degree in Criminal Justice from Stephen F Austin State University with minors in History and Sociology.
Officer Candoli served in the Austin Police Department (APD) for 27 years until he retired as a sergeant in 2021. While at APD, Officer Candoli served as a patrol officer in Northeast Austin, 6th Street, and then served many years on the APD SWAT Team before being promoted to the rank of sergeant. As a sergeant, Officer Candoli supervised a patrol shift, Lake Patrol, and then the Metro Tactical Unit (a street crimes unit). Officer Candoli is a certified TCOLE Instructor and a Firearms Instructor.
Steven Howell, Police Officer
Steven Howell joined Lake Travis ISD in September 2023. Prior to joining Lake Travis ISD, Officer Howell spent 33 years in law enforcement. He served with the Harris County Pct. 5 Constable's Office for 15 years, as a deputy, patrol sergeant and administrative sergeant. During this time, he created the Mountain Bike Patrol Division and the ATV Search and Rescue team.
In 2006, he moved to Lakeway, Texas, where he joined the City of Lakeway Police Department and served 2 years as a patrol officer. In 2009, he joined the Lower Colorado River Authority Police Department and became a Ranger on Lake Travis and responded to police calls from Lake Buchanan to Matagorda Bay.
In 2010, he returned to the Lakeway Police Department and served for 15 more years as a police officer and detective prior to his retirement. Officer Howell served as a Field Training Officer and Mental Health Officer at all three agencies.
Officer Howell graduated from the Lamar University Police Academy in Beaumont, Texas before moving to Harris County. After living in Lakeway for 14 years, he and his wife Sonia now live in Blanco County with their numerous pets and livestock.
Marianne Karlsen, Police Officer
Officer Marianne Karlsen was born and raised in Stavanger, Norway, the land of fjords. She came here as a high school exchange student in 1999 and knew she wanted to stay and make a life here. Marianne has been a proud American citizen since 2013 and she decided to pursue a career in law enforcement after being a stay-at-home mom to two boys for many years.
Officer Karlsen graduated from the CAPCOG regional police academy in 2014 and became a certified Texas police officer. Her previous experience includes working as a patrol officer for the Lakeway Police Dept., as well as serving as a court bailiff and at community events around Lakeway. Officer Karlsen is a certified Mental Health Officer.
When not working, Marianne enjoys spending time with her family and pets, horseback riding, gardening, and home decorating.
Andrew Kos
Andrew Kos, Police Officer
Officer Andrew Kos joined the LTISD Police Department with his partner K9 Zoe in September of 2025. Officer Andrew Kos brings over 32 years of law enforcement experience to Lake Travis ISD. Officer Kos obtained his bachelor’s degree in criminal justice from Texas Christian University with a minor in Psychology. During his time at TCU, Andrew played on the soccer team.
Officer Kos joined the Austin Police Department in January of 1994 and retired after 28 years of service in December of 2021. While at APD, Officer Kos served as a patrol officer in East Austin, worked in the tactical intelligence unit, served as a corporal, and ended his career as a detective. Officer Kos is a certified TCOLE Instructor, Field Training Officer, Marine Safety Officer, Mental Health Officer, and K9 Handler.
After retiring from Austin PD, Officer Kos spent a short time working as an officer for the Horseshoe Bay and Granite Shoals Police Departments from 2022-2024.
Officer Kos is currently LTISD’s K9 handler and is partnered with K9 Zoe. Officer Kos and K9 Zoe enjoy attending LTISD school events such as school sports and other school and community events.
Andrew is married to his wife, Seleste. They are the proud parents of Mikko, born in April of 2024 and their older kids Morgan, Zack, Nik and Sophia. The Kos house is ruled by 4 dogs (one of which is K9 Zoe). When Andrew is not working, he enjoys spending time with his family and dogs. Andrew's favorite activity is ice hockey where he enjoys playing, refereeing, and watching his kids play. He enjoys all sports, boating, K9 training, and supporting the Texas Stars and Dallas Stars hockey teams as well as all TCU sports.
Wendy Lopez, Police Officer
Wendy Lopez joined Lake Travis ISD in October 2023. Officer Lopez is originally from Eagle Pass, TX, where she graduated from Eagle Pass High School, and attended Southwest Texas Junior College.
Officer Lopez always had an interest in Law Enforcement, and in 2019 she joined the police academy. In 2020, Officer Lopez graduated from the Middle Rio Grande Law Enforcement Academy in Eagle Pass, TX. Officer Lopez joined the Lakeway Police Department in 2021, and she served for two years as a police officer in the patrol division before joining the LTISD Police Department.
When not working, Wendy loves to spend time with her family and enjoys fishing and hiking.
Valerie Medrano, Police Officer
Valerie Medrano was born and raised in Corpus Christi, Texas
Officer Medrano graduated from the Del Mar College Police Academy in 2016 and started her career as a patrol officer in 2017. Prior to relocating to Lake Travis ISD, she was employed at the Corpus Christi Independent School District Police Department for 7 years .
Officer Medrano has 2 kids she loves very much.
In her spare time, she stays active in the gym and loves to watch her son play football.
Martin Taylor, Police Officer
Officer Martin Taylor is a United States Air Force veteran with over 35 years of public safety experience, including a distinguished career with the Austin Police Department. While with the Austin Police Department, Officer Taylor worked in specialized units, including the Special Investigations Unit, Child Abuse, and Organized Crime, and was assigned to the United States Secret Service Financial Crimes Task Force. Officer Taylor holds a TCOLE Master Police Officer certification.
When not working, Officer Taylor enjoys spending time with his family and being outdoors.
K9 Zoe
K9 Zoe is a Belgian Malinois born in Poland in February 2022. She came to the United States in the spring of 2023. Zoe and Officer Kos began their partnership a short time later when Officer Kos joined Zoe at Pacesetter K9 in Liberty Hill, TX, for extensive training and certification. Zoe is nationally certified annually in narcotics detection and in tracking missing and lost persons.
Zoe and Officer Kos continue to train regularly with the Austin Police Department narcotics detection K9 teams and other K9 units from across the Central Texas area. Most of Zoe’s commands are in Czech, with a few in German and English. Prior to serving with LTISD, K9 Zoe and Officer Kos were a team with a small agency in the Marble Falls, TX, area.
Zoe loves attending LTISD sporting events, where she can often be seen wearing her Lake Travis red vest and collar, complete with specific patches for the different sports teams she supports. When not on duty, Zoe enjoys playing with Kong toys and spending time with her two husky siblings. She can be found on Instagram at k9_zoe_LT and on Facebook as Zoe the K9.