WAUKEGAN (CBS) — Lake County Coroner Richard Keller has pleaded guilty to two felony charges and will resign his position, effective immediately.

Keller pleaded guilty on Tuesday to obstruction of justice and unlawful delivery of a controlled substance, a release from the Lake County State’s Attorney’s office said.

The state’s attorney’s office began an investigation into Keller and his role as the director of the Green Dragonfly Methadone Clinic in Waukegan after the death of 30-year-old Steve Vaughn in 2008.

Keller had treated Vaughn at the clinic and also performed Vaughn’s autopsy after his death.

The investigation found the clinic was not in compliance with state and federal regulations, causing them to cease operations in September, 2009, a release from the state’s attorney’s office said.

In May, 2009, a series of grand jury subpoenas were issued for records from the clinic and in September, 2009, a search warrant was issued for all clinic records.

Records and documents were seized, which Dr. Keller had previously failed to turn over pursuant to the grand jury subpoena. Dr. Keller’s failure to turn over those records was the basis for his obstruction of justice charge, the release said.

The unlawful delivery of a controlled substance charge stems from a prescription Keller wrote as director of the clinic.

Lake County Sheriff Mark Curran will manage operations starting immediately, and continue until the county board appoints a replacement that would serve the remainder of the term, which ends in November 2012.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2010. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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