The K-9 Unit is responsible for tracking, evidence recovery, building searches, locating suspects, crowd control, drug and explosives detection, and canine demonstrations.

The Forensic Services Section — which on Sept. 17, 2011, became the first local law enforcement agency in Virginia to achieve accreditation from the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB) — operates from a specialized facility and is composed of three units:

• Crime Scene Unit (Responds to major crime scenes, details, collects and preserves evidence)
• Imaging Unit (Handles department photo requests, court exhibits and film processing)
• Fingerprint Unit (Evaluates prints from crime scenes, input of prints into NOVARIS and provide training)

It is the mission of the Bicycle Unit to work with the citizens of Prince William County to jointly resolve community problems that affect their quality of life. The Bicycle Unit proactively patrols the communities we serve and also assists with specialized enforcement activities and major events.

The Traffic Unit, familiarly known as “Motors,” is responsible for speed enforcement, the Roadway Incident Management Program (RIMP), the SMART Trailer deployment, and other special enforcement, such as traffic complaints and traffic-safety campaigns. Members of this Unit supply traffic direction at crash scenes and traffic-light malfunctions. They also work parades, other special events and provide escorts.

The Crash Investigation Unit is responsible for fatal crash investigations, hit-and-run investigations, inspections of commercial trucks, crash and crime scene reconstruction. The Unit also handles investigations involving serious personal injury.

The Special Weapons and Tactics Unit (SWAT) supports the Operations and Criminal Investigations divisions of the Department. This specialized unit attempts to resolve high-risk situations with a minimum loss of life, injury or property damage, and handles situations involving barricaded subjects, hostage rescues, suicidal subjects. SWAT also provides assistance on drug raids, arrest warrants and search warrants.

The Civil Disturbance Team is trained in active countermeasures to effectively deal with both hostile and passive crowds. The Team is deployed during planned demonstrations, and at large sports and entertainment venues in the County as needed. The Team also responds to aid requests from other law enforcement agencies in the region.

The Command Post Team responds to all major incidents where personnel are used for an extended period of time. The Mobile Command Post provides communications ability to interface with County police, fire and rescue, and public works personnel, as well as with emergency responders from jurisdictions throughout the region.

The Prince William County Police Department currently has three crime prevention officers and a civilian crime prevention specialist. All four have received Crime Prevention Specialist certification through the Virginia Department of Criminal Justice Services. They are highly trained in all areas of crime prevention, including personal safety, senior scams, active violence, home security, and identity theft.

The Honor Guard Unit provides official Departmental representation at funerals, dedications and other special events, and at the Police Recruit graduations, among other duties.

The Marine Unit maintains a 34-foot AMH Pilothouse vessel, which is docked at the Belmont Bay Harbor Marina on the Occoquan River. Its main patrol areas are the Occoquan and Potomac rivers, but the unit can routinely patrol other inland waterways and lakes.

The Mounted Patrol Unit provides specialized services in the areas of search and rescue, crime prevention and crowd control. The Unit was formed with the goal of bringing residents and police together to keep our communities safe. Seizure funds taken from the assets of drug dealers enabled the Unit to purchase equipment, including uniforms, horse blankets and a horse trailer.

The Underwater Search & Recovery Team (USRT) — popularly known as the Dive Team — is activated to recover drowning victims and to search for, and recover, evidence in criminal investigations.

The Search and Rescue (SAR) Team is part of the Special Operations Bureau and supports both the Operations and Criminal Investigations Divisions of the Department.  When activated, the SAR Team is responsible for the coordination of active search and rescue operations for missing and endangered subjects, as well as locating and recovering item(s) of evidence.  The SAR Team is designed to be self-sufficient on any mission it is called upon to handle.