Reviewed and updated October 9, 2026 by the SearchSystems.net editorial team. The arrest counts are the ones the agency reported to the FBI, through 2025. The jail figures are from the Vera Institute of Justice's Incarceration Trends data. Every office link was opened and checked against the office's own site between September 23, 2026 and September 25, 2026.
Thornton, Colorado, in Adams County, has about 147,000 residents (2024 Census Bureau estimate), and its arrests are reported to the FBI by an agency of its own. An arrest in the city leaves the same records whoever makes it: the arresting agency's report, the record of anyone held at the county jail, and, if the District Attorney files charges, a case in the Adams County District Court. This guide says who keeps each one, what it costs and who may see it, with the arrest counts the agency reported.
This guide covers who makes arrests, how many arrests, booking and the jail, finding an arrest, copies and common questions.
Related guides: Thornton public records, Adams County arrest records, Colorado arrest records and Colorado inmate search.
Who Makes Arrests in Thornton
The FBI lists Thornton with an arrest reporting agency of its own, filed as Thornton Police Department. It reported 5,705 arrests for 2025. A city is listed separately whether the officers are the city's own or the sheriff's under contract; the FBI's list does not say which.
Outside the city, the Adams County Sheriff's Office is the county agency. It reported 6,472 arrests for 2025.
The FBI's agency list also places one more agency in Adams County: the University of Colorado at Denver (campus police).
How Many Arrests Thornton Reports
Each agency reports its arrests to the FBI by month, and the FBI publishes them on the Crime Data Explorer. These are the full-year totals, all offenses, as the FBI held them on October 8, 2026; a year with months missing or not reported is left out.
- Thornton: 5,705 for 2025, 5,188 for 2024, 5,136 for 2023, 5,109 for 2022, 3,966 for 2021 and 3,577 for 2020.
Thornton's 5,705 arrests in 2025 were up 10 percent from 5,188 in 2024.
Through August 2026, Thornton reported 4,046 arrests, against 3,807 in the same months of 2025.
Across Adams County, the seven agencies with all twelve months of 2025 on file reported 21,118 arrests between them.
Booking: Where People Arrested in Thornton Are Held
A person kept in custody after an arrest in Thornton is held at the county jail, whichever agency made the arrest, apart from the short stay some city departments' own holding cells allow; a person cited and released at the scene is not booked at all. The jail's record of each person held, with the charges, is a public record of the arrest, and the court file takes over from there.
On an average day in 2025 the jail held about 780 people, down from about 990 in 2019. Its rated capacity in 2025 was 1,197 beds, and it ran at 65 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
SearchSystems opened and checked the custody page of the Adams County Sheriff's Office at adamssheriffco.gov/community/public-records/inmate-search (page title: Inmate Search | Adams County Sheriff Office), phone (303) 288-1535, Monday - Friday, 8:00am - 5:00pm., which answered when SearchSystems opened it on September 23, 2026.
That page is the place to look for someone who was booked recently; a person cited and released at the scene, or held only a few hours by a city department, will not be on it.
A person sentenced to prison serves the sentence in a facility of the Colorado Department of Corrections, whose inmate locator is at cdoc.colorado.gov.
How to Find Out About an Arrest in Thornton
Whether someone was arrested in Thornton, and what came of it, shows up in two places: the custody page of the Adams County Sheriff's Office described above, for anyone booked into the county jail; the case index of the Adams County District Court, which shows whether charges were filed and the next court date (the court records page SearchSystems verified is at coloradojudicial.gov/courts/trial-courts/adams-county, phone 303-659-1161).
Colorado is one of the states that lets anyone look up another person's statewide criminal history: the state runs an online name-based criminal history check open to the public, through the Colorado Bureau of Investigation. That record shows what agencies reported to the state, which is wider than one county's court index but can lag it.
Getting a Copy of an Arrest Record in Thornton
An arrest report belongs to the agency whose officer wrote it, and that agency releases it, not the court or the jail. Under the Colorado Open Records Act the agency must answer within 3 working days, extendable to 7 when there are extenuating circumstances, and it may charge research and retrieval time after the first hour, plus copying.
- An arrest by the Thornton police: the police records page SearchSystems verified at forms.thorntonco.gov/Police/RequestForCriminalJusticeInformation (page title: Request For Criminal Justice Information | Thornton Police Department | Thornton Forms), phone 303-538-7230, which answered when SearchSystems opened it on September 25, 2026.
- An arrest by the Adams County Sheriff's Office: ask its records unit, reached through the office at (303) 288-1535.
- The court file of a case that was filed: the Adams County District Court, through the court records page at coloradojudicial.gov, phone 303-659-1161.
- Your own statewide record: a name-based or fingerprint-based request to the Colorado Bureau of Investigation.
The Adams County guide covers every agency in the county: Adams County arrest records.
Frequently Asked Questions
How many arrests are made in Thornton each year?
Thornton reported 5,705 arrests to the FBI for 2025, its latest full year.
How do I find out if someone is in jail in Thornton?
Look on the custody page of the Adams County Sheriff's Office at adamssheriffco.gov, or call (303) 288-1535. It covers people booked into the county jail.
Where are people arrested in Thornton booked?
Those kept in custody go to the county jail, run by the Adams County Sheriff's Office; a person cited and released at the scene is not booked.
Are arrest records public in Thornton?
The court files of criminal cases are public, and so is the statewide criminal history kept by the Colorado Bureau of Investigation: the state runs an online name-based criminal history check open to the public. The arrest report itself is released by the agency that made the arrest, under the Colorado Open Records Act.
How do I get a copy of an arrest report in Thornton?
From the agency that made the arrest: the Thornton police for its own arrests, the Adams County Sheriff's Office for the sheriff's. Under the Colorado Open Records Act the answer is due within 3 working days, extendable to 7 when there are extenuating circumstances.
Is this the official Thornton website?
No. SearchSystems.net is an independent public records guide, online since 1997. It links to the official city, county, court and state offices described above and does not hold records, charge for them or take requests.