Audit finds invoicing gaps and some overbilling in Wayne County sheriff's residential treatment program

The Wayne County Committee on Audit on May 1 received a performance audit that found weaknesses in controls over the Sheriff’s Office community‑based residential rehabilitation treatment (CBRRT) program, including inconsistent attendance records, a lack of invoice validation and sample overbillings totaling $6,150.

The audit, presented by Legislative Auditor General Marcy Cora, examined calendar years 2022 through 2024 and tested invoices and attendance records. "We identified 4 issues and had 11 recommendations to strengthen the sheriff's internal controls over the CBBRT program," Cora said. The audit classified one finding as a material weakness and one as a significant deficiency.

The report said three of four contracted providers submitted attendance or sign‑in sheets inconsistently (missing dates, times or signatures) and one provider recorded attendance only in progress notes. The audit team recommended that Wayne County Sheriff’s Office management require standardized attendance sheets and that providers submit those sheets with monthly invoices to support billed days.

Chief Robert Dunlap of the Wayne County Sheriff’s Office acknowledged the problems identified and said his office had already begun internal work before the audit. "When the recommendation came to confirm that we had attendance sheets that accompany every invoice that come back, certainly, we agreed because it was something that we had already identified," Dunlap said. Director of Administration Vanita Terry told commissioners the sheriff’s office has issued a spreadsheet template tied to the attendance sheets and that vendors now report billing on that spreadsheet.

The audit also found a lack of a method to validate provider invoices against supporting documentation and recommended written policies and procedures to validate monthly invoices, a standardized attendance sheet to be submitted with each invoice, and consideration of a modification to the jail management system (JMS) to track provider assignments and participant entry/exit dates. Cora emphasized that those steps should be codified in policy so future staff follow the same processes.

The audit tested a sample of 24 participants on 12 invoices and found the providers in the sample overbilled the sheriff's office by $6,150. Because the sample represented about 20% of 63 invoices in the scope period, auditors warned the total overbilled amount could be higher; extrapolation of the sample suggested a potential scale in the tens of thousands. The audit recommended assigning dedicated personnel to invoice reviews and conducting periodic audits to identify and correct discrepancies.

Chief Dunlap said his office began an internal investigation in early 2023 and has taken steps to recover overpayments. "We have, in fact, overpaid some of the vendors," he said, adding his office had recovered about half of the overpayments identified in 2022 but did not provide an exact dollar amount at the meeting.

Commissioners pressed for clarity on recoupment and scope. Commissioner Garza asked how far back a review should go; auditors and sheriff's staff said the county must weigh cost‑benefit and statute‑of‑limitations issues when deciding how many prior years to audit. Certified letters notifying vendors of identified overpayments were sent and the sheriff’s office reported applying credits against future invoices while rebuilding records that were partly affected by a later cyberattack.

Other substantive program controls discussed at the meeting included administrative jail release documentation and eligibility. The audit sampled administrative jail release forms and found missing or incomplete notations of mental health or substance use disorder status and inconsistent signatures; it recommended a review process to ensure required fields are completed before referral to treatment. Commissioners and staff noted that acceptance into the program requires documented mental health or substance use disorder status and that a signed attestation indicates the participant understands possible consequences for noncompliance.

The committee also discussed program design and funding mechanics: the audit team and sheriff's staff said the county reduced the program’s maximum billed residential days from 90 to 45 based on provider guidance and to stretch funds. Some participants are connected to Detroit Wayne Integrated Health Network (DWIN) funding or Medicaid after release; when providers obtain that outside funding, they should stop billing the sheriff’s residential treatment fund.

Commissioner Killeen asked whether reincarceration occurs after program noncompliance; Chief Dunlap said that happens occasionally and that jail‑based services are more limited than those available through the CBRRT program. Commissioner Knisek praised the collaborative approach: "I think it's a really good thing," she said, in reference to auditors and sheriff's staff working together on corrective actions.

The Committee on Audit voted to receive and file the audit. Commissioner Garza moved to receive and file the report; Commissioner Killeen supported the motion and the chair announced the motion carried.

The audit included 11 recommendations and management agreed to all. Commissioners requested a corrective action plan and follow‑up within 30 days after the full board receives the report. The sheriff's office said it will document policy changes, continue invoice verification procedures, pursue recoupment where feasible, and implement periodic audits and staff assignments to reduce future risk.

Questions about precise recovery amounts, the cost to modify JMS, and the number of prior years to review remained open; commissioners asked staff to return with those details as part of the corrective action and budget planning process.