Investigations Division

The Investigations Division investigates serious or major crimes occurring in the unincorporated areas of Marin County. The division also provides technical and manpower assistance for major crimes to the city police departments when requested. This division is comprised of nine groups which are divided into four Sheriff’s Office investigative units, four multijurisdictional investigative units and a property/ evidence unit.

The first four Sheriff’s Office teams include adult, juvenile, crime scene and cold case investigative units.  The multijurisdictional units include the Specialized Investigative Unit, the Coordination of Probation Enforcement Unit and the Marin County Auto Theft Task Force.  Also under the umbrella of the Investigations Division is a sergeant assigned to the Northern California Regional Intelligence Center. The Investigations Division  is overseen by Lieutenant Brian Fay.


Adult Crime Unit

Adult Crimes

The Adult Crime Unit consists of one sergeant and three detectives.  The Adult Crimes Unit is responsible for investigating all serious crimes to include homicide, robbery, property crimes, and crimes against persons.

Detectives provide a coordinated response to the various crime scenes that are encountered throughout the county.  Detectives complete both preliminary and follow-up investigations.  Detectives also conduct research to establish common links between crimes and seek to identify / arrest each offender.  Detectives in the unit have received extensive training related to death investigations, search and seizure, search warrants, evidence collection and preservation, interviewing, intelligence gathering and the legal process.

Juvenile Unit

Juvenille Unit

The Juvenile Unit is comprised of two child abuse/sexual assault detectives, one School Resource Officer, and one sergeant. The unit is responsible for investigating child abuse, sexual assault, vice crimes and juvenile delinquency. Detectives receive numerous hours of specialized training to address all manner of crimes committed against children.

The Sheriff’s Office is committed to the multi-disciplinary approach when investigating cases of sexual exploitation of children. Detectives from this unit work closely with the District Attorney, Children and Family Services, the Jeannette Prandi Children’s Center and other treatment providers. 

The Juvenile Unit, under the umbrella of the Marin County Sheriff’s Office is a member of the Region II Regional SAFE Task Force. SAFE stands for Sexual Assault Felony Enforcement. This task force is a cooperative arrangement with 11 other Bay Area counties. The primary objective of the Region II Regional SAFE Task Force is to reduce the rate of non-compliance among registered sex offenders and provide educational programs to the community as they relate to registered sex offenders. This taskforce works together to investigate and monitor registered sex offenders, conduct compliance checks and surveillance, and seeks to ultimately protect the community.

The Juvenile Unit also partners with agencies across the bay area to combat Internet Crimes Against Children (ICAC).  As a part of a regional ICAC Task Force the Juvenile unit seeks to identify, apprehend and prosecute Internet sexual predators who exploit children through the use of computers.  The Juvenile Unit also sponsors community education efforts regarding the prevention of Internet crimes against children.

The School Resource Officer, Deputy Devon Gasparini is responsible for addressing concerns and referrals involving juveniles in Marin County Schools. This unit also administers the Juvenile Diversion Program and coordinates the School/Law Enforcement Partnership with the Marin County Office of Education.


Crime Scene Investigation

Csi Detective

The Crime Scene Investigation (CSI) unit is comprised of two Detectives.  The CSI unit is responsible for, but are not limited to, photographing, analyzing, collecting evidence, reconstructing major crime scenes, assisting deputies and other agencies with crime scene processing, analyzing fingerprints and operating the CAL-ID computer which searches the State’s fingerprint database. In addition to CAL-ID, the unit also operates a County wide AFIS system for searching latent fingerprints.

The CSI unit also runs a latent fingerprint laboratory where evidence collected at a crime scene is processed for latent prints. Processing includes cyanoacrylate (superglue) fuming, black powder and magnetic powder processing, ninhydrin processing and the use of A.L.S. and fluorescent powders.

Cold Case Team

Marin County Cold Case

The Sheriff’s Office Investigations Division also oversees a Cold Case Team.  The Cold Case Team was established in 2012 to focus investigative efforts on unsolved homicides.  The team is currently staffed on a volunteer basis by three retired former prosecutors from the Marin County District Attorney’s Office.  

During their methodical review of each case, the information is organized and examined for new avenues of investigation, including the latest advances in the field of forensic science.  The Cold Case Team routinely reviews investigative leads and intelligence for possible connection to homicides.  During their first year with the Sheriff’s Office, the Cold Case Team helped the District Attorney’s Office with the pretrial preparation and jury trail of serial killer Joseph Naso.

Property Unit


The Property Unit maintains the evidence and property submitted by our Deputies and Detectives. This includes, but is not limited to, items of evidence in criminal matters, evidence seized in narcotic related investigations, found property and firearms that are turned over to the Sheriff’s Office to be destroyed.

There are two persons in our Property Unit.  Our Property Unit is in charge of receiving the property and evidence; maintaining the files and records regarding the storage, movement and disposition of property in her custody; releasing evidence to the courts for trials; testifying in court as to the chain of custody of evidence; releasing property to its rightful owner; making sure property is properly destroyed when the disposition requires; arranging for the sale of unclaimed property to the public through an authorized auction house and the safe handling and destruction of bio-hazard materials. If you need to claim property that has been taken as evidence and there has been a final disposition in the court case or you want to claim found property in our custody, please call 415-473-6820 and make an appointment with Christine. Please do not just stop by. Making an appointment assures that someone will be here to assist you.

Coordination of Probation Enforcement


The main focus of the C.O.P.E. unit is to monitor high risk narcotic violators who have been placed on probation, rather than serving time in custody. The goal of the C.O.P.E. unit is to ensure that those individuals who have been granted the privilege of probation are leading law abiding lives while they are serving their probation term. As a term of their probation sentence, these individuals have waived their 4th Amendment right to search and seizure. The C.O.P.E unit carries out unannounced probation checks of these individuals in an attempt to ensure they are abiding by the terms of their release. The unit also conducts investigations into street level narcotics dealers and assists the Specialized Investigative Unit with their narcotic investigations. 

The C.O.P.E. unit was started in 1990 and originally staffed with a Sergeant and a Deputy from the Sheriff’s Office and a Marin County Probation Officer. The unit is currently staffed by a Sheriff’s Sergeant, a Sheriff’s Deputy, a Novato Police Officer, and a Marin County Probation Officer.

The C.O.P.E. unit has countywide jurisdiction. They work with all of the agencies within Marin County and often receive information from the various police departments regarding probationers who require special attention.

Specialized Investigative Unit

Marin County Siu

The Specialized Investigative Unit (SIU), working under the command of the Sheriff’s Office Investigations Lieutenant, takes a proactive approach to investigate narcotics related criminal activity.  The SIU is directly supervised by a Sheriff’s Office Sergeant who works in the capacity of an assistant commander of the unit.  The unit is comprised of detectives from the Marin County Sheriff’s Office, the Central Marin Police Authority, the Novato Police Department, the California Highway Patrol as well as an agent from the Drug Enforcement Administration.

While the SIU primarily investigates narcotics related criminal activity the unit also assists with the investigations of violent or major crimes when the specialized skills of SIU personnel are requested by the agencies represented in the SIU.  SIU personnel primarily work in an undercover capacity and are highly mobile to work within or outside of the county of Marin.

Marin County Auto Theft Taskforce

Marin County Auto Theft Taskforce

The Marin County Auto Theft Taskforce primary mission is to reduce the incidence of vehicle theft while increasing the apprehension rates of the professional vehicle thief.  MCATT accomplishes its mission through proactive investigative methods and by providing vehicle theft training to allied agencies.

MCATT is coordinated through the Marin County Sheriff’s Office and managed by the Investigations Division Lieutenant.  MCATT is supervised by the SIU Sergeant and comprised of law enforcement personnel from the Sheriff’s Office and CHP.