Jerry Kerber, a steadfast public servant who recovered tens of millions of dollars for taxpayers while cracking down on fraud in Minnesota's health and welfare programs, is retiring this month after 38 years in state government.

Known for his unrelenting energy and no-nonsense approach, Kerber, 61, was widely credited with transforming a sleepy fraud and abuse division at the Department of Human Services (DHS) into an aggressive, high-profile unit. He testified at the State Capitol regularly on the millions of dollars in Medicaid overpayments his unit had recovered from illicit providers, and the Legislature responded by greatly expanding his staff.

Kerber took over five years ago as the first inspector general at DHS, a massive state agency with an $18 billion annual budget. He quickly expedited investigations of maltreatment at facilities that serve nearly 300,000 of Minnesota's most vulnerable residents, broadened oversight of health care providers that receive public funds, and took steps that dramatically cut infant deaths at home-based child care providers, among other accomplishments.

"What can be more fulfilling than being part of a team that is dedicated to assuring that children and vulnerable adults are safe — and that they are getting the services they need, that we pay for, and that are provided by the right people," Kerber wrote in a note last week to staff.

His last day as inspector general will be Oct. 18. The agency has not selected a replacement.

Since late 2014, Kerber's office has conducted hundreds of unannounced, on-site screenings of Medicaid doctors and clinics and has initiated fingerprint background checks on tens of thousands of health care and social service workers statewide. Once criticized as soft on fraud, DHS has more than doubled the sums recovered from fraudulent overbillings of Medical Assistance, the state's publicly funded health plan, since 2011. All told, the DHS inspector general has recovered $69 million in Medical Assistance overpayments under Kerber's tenure, and has completed 3,200 investigations into inappropriate billing.

In addition, Kerber forged closer ties with federal law enforcement officials as part of a sustained investigation into fraudulent billings in the state's child care assistance program for poor families. Investigators have since uncovered multiple schemes, reaching into the millions of dollars, in which child care providers exploited poor parents to obtain more state payments.

Still, in an interview Thursday, Kerber insisted, "We're not just about catching people." His office also made internal advances, such as improving the speed and accuracy of background checks to prevent criminals from getting licensed and billing public health programs. The state, for instance, can now automatically detect when a home care aide bills the state for more than 24 hours of service in a day.

"Things are in good shape here," Kerber said. "The ultimate decision that people make about when to retire ends up being a combination of work-related and private life needs. This just seemed to be the right time."

Kerber began his state career in 1978 working with children experiencing emotional disturbances in what was then the Brainerd State Hospital. He then worked in mental health treatment at the state prison in Stillwater and the Anoka-Metro Regional Treatment Center, before moving in 1988 to the licensing division at DHS, where he became director. He was appointed DHS inspector general in August 2011, when the office was created; the unit has since nearly doubled, to about 225 employees.

"Jerry brought an enormous amount of passion to the job every day, and never lost sight of the fact that licensing is about the people being cared for," said Anne Barry, former deputy DHS commissioner who worked with Kerber for 25 years. "It breaks my heart to see him leave."

Twitter: @chrisseres