Search Marin County Inmate Population

Marin County Inmate Population Snapshot

The Marin County inmate population starts with the adult county jail in San Rafael. The Marin County Sheriff's Office Custody Division describes the jail as the local facility for adults booked for law violations, people serving Marin County jail terms, some state-prison terms served locally, and short enroute holds. San Quentin Rehabilitation Center is also inside Marin County, but it is a CDCR state prison, not part of the county jail roster. Marin County Juvenile Hall is a separate youth facility run by Probation.

That split matters. The Marin County inmate population count can mean current county jail custody, a state-prison population physically located in Marin, or restricted juvenile detention. For local jail trend work, the strongest sources are the Sheriff's custody page, the 2025 PREA audit, and the California BSCC Jail Profile Survey dashboard. For state-prison custody at San Quentin, use CDCR population reports and CIRIS.

Marin County Inmate Population Statistics

Official Marin County sources do not use one single capacity number in every record. Public Works and the 2024 Civil Grand Jury describe 222 cells and 385 beds. A 2024 county RFP used 376 jail beds, while a 2025 Civil Grand Jury reentry report used 325 as total bed capacity. The safest reading is to treat 385 as the physical bed count, while explaining that classification, mental-health needs, single-cell placements, gang separation, and AB 109 realignment reduce usable operating space.

The state-prison number should not be merged into the county jail total. San Quentin's population is much larger than the jail population and is governed by CDCR sentencing, classification, and transfer rules. It belongs in the Marin County facility map because the prison is in the county, but not in the same jail roster search.

Marin County Jail Population Trends

The 2025 BSCC monthly data gives a useful view of the Marin County inmate population across a full year. Monthly average daily population ranged from 240 in December to 281 in July. Monthly bookings ranged from 443 in February to 588 in July. Felony ADP was higher than misdemeanor ADP in every captured month, and non-sentenced males made up the largest category each month.

The pattern is not a simple overcrowding story. The 2025 PREA audit reported no over-capacity condition in the prior 12 months. At the same time, the 2024 Civil Grand Jury found pressure from single-cell needs, mental-health classifications, substance-use issues, gang separation, AB 109 longer jail stays, and the underground jail design.

The BSCC dashboard screenshot below is the state source used for California local jail profile data, including Marin monthly jail population reporting.

BSCC data is most useful for trend comparison. For a current individual custody lookup, the Marin County Public Booking Log remains the direct starting point.

Marin County Jail Capacity

The Marin County Jail opened in 1994 on the Civic Center grounds. Civil Grand Jury material describes a hub-and-spoke design with three floors, six direct-supervision pods, 222 cells, and a hillside or underground setting meant to protect the view of the Frank Lloyd Wright Civic Center. That local design detail explains why the Marin County inmate population can be below the physical bed count while still creating daily pressure for staff, programs, and housing assignments.

Classification is the key word. In jail use, classification means the safety and housing process that separates people by sex, charge type, risk, medical need, mental-health need, gang concerns, protective custody, and other factors. A cell with two bunks may not be usable for two people if those factors require separation. The Grand Jury also noted limited program rooms, small recreation yards, and medical and mental-health space limits. The Sheriff response disputed some findings and cited annual Title 15 and Title 24 compliance plus recent infrastructure work.

Classification

Jail housing and safety assignment based on risk, health, charge, and separation needs.

ADP

Average daily population, a monthly or yearly measure of how many people are held on a typical day.

AB 109

California realignment that shifted some lower-level felony terms from state prison to local custody.

Remand

A court order keeping a person in custody instead of releasing them while the case proceeds.

Marin County Inmate Data Laws

Public access to the Marin County inmate population is controlled by a mix of California public-records law, jail standards, booking-photo limits, and court timing rules. The county booking log says its data is released under the California Public Records Act, using the older law-enforcement citation that appeared before CPRA recodification. Current CPRA provisions still matter because they frame public inspection and exempt records.

Search Marin County Jail Custody

The Marin County Public Booking Log is the official online channel for current adult county jail custody. It covers people arrested and booked into the Marin County Jail in the last 48 hours who are still in custody, plus the current jail list at the time the search is run. It is not a full archive of old bookings or released inmates.

The public booking log screenshot below shows the official search page and its current-custody framing.

The log is useful when the person is still held at Marin County Jail. If the person has been released, transferred, or sentenced to state prison, another channel is needed.

1. Open the Public Booking Log rather than a general web search.
2. Enter the last name if known, or review the current list if the live interface permits it.
3. Compare the booking agency, charges, bail notice, and next court date details when shown or confirmed by jail staff.
4. Call the jail information line if the person does not appear and the arrest was recent.
5. Use CDCR, BOP, ICE, or court records if the case moved outside current county jail custody.

When Marin Roster Search Fails

A failed roster search does not prove the person was never arrested. The person may have been cited and released, released before the search, held under a different spelling, transferred to another agency, sentenced to CDCR, or placed in a restricted juvenile process. Marin Sheriff materials say jail staff give information only on current in-custody people, so older booking records route through the Records Division rather than the live roster.

Marin County Detention Facilities

Three facilities shape the Marin County inmate population picture, but each serves a different legal system. The adult county jail is the local roster source. San Quentin is a state prison with CDCR lookup rules. Juvenile Hall is a youth facility with restricted records and no public juvenile roster.

• Marin County Jail holds adults booked for Marin law violations, jail sentences, some local state-prison terms, and temporary enroute holds.
• San Quentin Rehabilitation Center is a CDCR state prison for sentenced incarcerated people and is searched through CIRIS.
• Marin County Juvenile Hall is a short-term youth detention and supervision facility, not an adult jail roster source.

County Jail vs State Prison

The Marin County inmate population search is easiest when the custody type is identified first. A recent local arrest points to the county booking log. A state-prison sentence points to the CDCR CIRIS locator. A federal sentence points to the BOP Inmate Locator. Immigration custody uses ICE ODLS. VINELink is useful for notice of custody changes, but it is not a substitute for the official roster or locator.

No dedicated Marin Sheriff custody app was located in the research pass. County service apps such as FixItMarin and SCRAM Touchpoint serve non-custody or pretrial check-in functions, not an inmate roster.

Marin County Records After Release

Older Marin County inmate records are handled differently from current custody. Sheriff Records Division is the local repository for booking records and can receive requests by mail or fax, but individual records must be picked up in person and valid ID must be shown. Court dispositions are not jail records. The Sheriff directs those questions to Marin Superior Court.

After arrest, the legal case begins when the District Attorney files charges in Marin Superior Court. Court users can search the ePortal or submit a records request to Court Records and Exhibits. Court records may include filed complaints, parties, hearings, disposition details, and documents when public access rules allow them. Confidential, sealed, and juvenile records are restricted.

Marin Jail Programs and Oversight

Population data also connects to reentry and conditions. Marin County HHS identifies Jail Behavioral Health Services and Jail Re-Entry Services for people leaving custody with treatment or healthcare needs. Civil Grand Jury material described education, addiction counseling, parenting, church services, AA, NA, mindfulness, anger management, and mental-health programming, while also noting that the building layout limits program space.

The 2024 Civil Grand Jury report raised concerns about the jail's underground design, limited light and air, program limits, medical and mental-health space, and the need to study a broader justice-center model. The Sheriff response disputed parts of the report and cited annual state compliance inspections and recent infrastructure upgrades. Marin County also launched a Sheriff's Civilian Oversight Commission and, in 2026 reporting, hired its first Inspector General.

Marin County Inmate Population FAQ

How large is the Marin County inmate population?

The county jail population is usually measured separately from San Quentin. Marin Sheriff's 2022 ADP was 245, the 2025 PREA audit reported ADP of 251, and BSCC 2025 monthly ADP ranged from 240 to 281. San Quentin had 2,346 people in the CDCR TPOP1 report dated May 27, 2026.

How do I search current Marin County inmates?

Use the Marin County Public Booking Log for current adult county jail custody. If online bail appears, treat it as approximate and call the jail for exact bail information. If a person does not appear, check release, transfer, court, state-prison, federal, ICE, or juvenile possibilities.

Does the Marin roster include released people?

The booking log is not a historical inmate archive. It covers current custody and recent bookings only when the person is still in custody. Older booking-record requests route to Sheriff Records Division, while filed charges route to Marin Superior Court.

Is San Quentin part of the Marin jail roster?

No. San Quentin Rehabilitation Center is in Marin County, but it is operated by CDCR. Search CDCR CIRIS by name or CDCR number for sentenced state-prison custody.

Are juvenile records public?

Marin County Juvenile Hall is not an adult jail, and no public juvenile roster was located. Parents, guardians, counsel, Probation, and Juvenile Court are the proper channels for youth detention questions.