Mercer County, Ohio — The Jail, the Sheriff, the Judges

The Detention Center

Mercer County Detention Facility

Operated byMercer County Sheriff's Office, Corrections Division
Jail address4835 State Route 29, Celina, OH 45822
StaffingMinimum of three corrections officers per shift; inmates monitored 24 hours a day
2025 average daily population54 in January, ranging from a low of 7 in February to a high of 97 in April
2025 corrections budget$3,061,421 — $2,244,000 salary, $388,500 benefits and training, $428,921 materials, equipment and supplies
Holding other agencies' prisoners230 inmates held for other agencies in 2025, producing $170,850 in revenue
VisitationNon-contact video visitation, scheduled through cidnet.net

Source: Mercer County Sheriff — Corrections · checked 2026-09-20

Transparency rating

5/10Partial

✓The jail is named
✓Who is in custody
✓Beds and daily population
✓What it costs taxpayers
✗Deaths in custody — not published
✗PREA audits — not published
✗Independent inspection — not published
✓Who else it holds, and for how much
✗How to post bond — not published
✗Phone, video and commissary rates — not published

This rates disclosure, not conduct — what Mercer County publishes about a jail its taxpayers own, checked 2026-09-20. Nothing here says the jail is run well or badly. Every mark moves the moment the county posts the document.

The Building

You paid for it. Here is what the record says it cost.

Year builtNot found
Original costNot found
Paid for byNot found
BedsNot found — no rated capacity is published; the 2025 annual report gives monthly average daily population instead

Since then

Not found

The Sheriff

Sheriff Doug Timmerman

Runs the jailYes — the sheriff's Corrections Division operates the Mercer County Detention Facility
How the office is filledElected, four-year term (Ohio Rev. Code 311.01)
Office address4835 State Route 29, Celina, OH 45822

Still needed

Detention budget requested vs. approved, by year
Jail staffing levels and vacancy rate
Lawsuits and settlements involving the jail

Source: Mercer County Sheriff's Office · checked 2026-09-20

The Judges

Ohio common pleas judges are elected to six-year terms; municipal and county court judges also set bail for people arrested in their areas. They are state judicial officers, not county officials.

Mercer County Circuit Court

Mercer County Common Pleas Court
Mercer County Probate/Juvenile Court

Still needed

The county's bond schedule
Share of the jail population held pretrial
Median time from booking to first appearance

Source: the state judiciary · checked 2026-09-20

The County Commissioners

They pay for the jail. The sheriff runs it.

What they controlThe jail budget, the building itself, and the agreements that send prisoners to a regional jail or rent beds to other agencies. In Cuyahoga and Summit, the elected County Executive and County Council.
What they don'tDay-to-day operations. The sheriff is separately elected and has charge of the county jail by state law (Ohio Rev. Code 341.01) — unless the county uses a regional jail run by a multicounty board.
NoteThree-member board: Brian Miller, Rick Muhlenkamp and Dave Buschur. The board's fiscal-data page publishes annual appropriations back to 2008.
The boardMercer County Board of Commissioners →
Where the jail money is decidedAgendas and minutes →

Notes on the record

Mercer County is the most open county in this group. The sheriff's site is on a county domain, mercercountysheriffohio.gov, and hosts its own inmate roster at inmate.mercercountysheriffohio.gov, which opened and showed 71 people in custody with names, ages and photographs but no bond amounts.
The sheriff publishes annual reports back to 2017. The 2025 report gives the jail's monthly average daily population, the $3,061,421 corrections budget, and the fact that 230 inmates were held for other agencies during the year for $170,850 in revenue — which is what earns the contracts check.
The county's own fiscal-data page publishes appropriation summaries back to 2008; the 2026 summary opened and shows a Sheriff line at $3,738,156 and a separate Jail line at $765,000.
No rated bed capacity is published anywhere on the sheriff's site; the capacity check rests on the published daily population figures instead.
No PREA material, deaths-in-custody record, inspection copy, bond guidance or fee rates appear on the sheriff's or the county's pages opened; the visitation rules page sets conduct and dress rules but names no charges.
State inspection/oversight: Ohio's Department of Rehabilitation and Correction, through its Bureau of Adult Detention, inspects full-service county jails each year against the Minimum Standards for Jails in Ohio (Ohio Adm. Code 5120:1-8) and publishes the reports on its own website.

These three offices decide who sits in a cell in Mercer County and what it costs the people who live here. Nationally, almost 77% of the people who died in local jails in 2019 had not been convicted of anything, and suicide was the leading single cause of those deaths (Bureau of Justice Statistics, Mortality in Local Jails, 2000–2019).

How much is your sheriff — and your judge — costing you?

Your VOTE is POWERFUL.

The sheriff who runs this jail is elected. So are the commissioners who pay for it.

Names verified 2026-09-20 · dollars and outcomes still being gathered