PLATTEVILLE, Wis. — A joint law enforcement operation in Grant County culminated on May 6, 2026, with the execution of search warrants at a residence on 230 W. Gridley Ave. in the City of Platteville, resulting in two arrests on multiple drug and theft-related charges and the recovery of a stolen vehicle.

The Grant County Sheriff’s Office initiated the search as part of an ongoing investigation into a stolen vehicle. During the operation at the Platteville home, deputies discovered an active marijuana grow operation, a substantial quantity of processed marijuana, methamphetamine, extensive drug paraphernalia, as well as multiple firearms and ammunition.

Authorities also located the stolen vehicle during the search of the property. With assistance from the Iowa County Sheriff’s Office, the vehicle was successfully recovered in the Town of Mineral Point.

Two Platteville men taken into custody

Dennis Medley, 67, the homeowner, and his roommate Jeremy Kastner, 50, were both arrested at the scene and transported to the Grant County Jail.

Medley faces the following charges:

•  Maintaining a Drug House

•  Manufacturing Marijuana

•  Possession with Intent to Deliver Marijuana

•  Possession of Methamphetamine

•  Felon in Possession of a Firearm

•  Receiving or Concealing Stolen Property (valued over $10,000)

•  Possession of Drug Paraphernalia

Kastner was arrested on charges of:

•  Receiving or Concealing Stolen Property (valued over $10,000)

•  Possession of Drug Paraphernalia

•  Three counts of Bail Jumping (related to an open case from 2025)

Multi-agency effort

The Grant County Sheriff’s Office was assisted in the operation by the Richland-Iowa-Grant Drug Task Force, the Platteville Police Department, and the Iowa County Sheriff’s Office.

Law enforcement officials have not released additional details about the scale of the marijuana grow or the specific types and quantities of items seized, citing the ongoing nature of the investigation.

Standard legal note

As is standard in Wisconsin law enforcement releases, all persons arrested or referred for charges are presumed innocent until proven guilty in a court of law. An arrest indicates only that probable cause exists to support formal charges. Names of any victims or witnesses have been withheld in accordance with Wisconsin Statute §950.04.

This case highlights ongoing regional efforts to combat drug manufacturing and trafficking in southwestern Wisconsin, where multi-agency drug task forces frequently collaborate with local sheriff’s offices and police departments on cases involving both narcotics and property crimes.

No further information about potential additional suspects or the full scope of the stolen property investigation has been released as of May 8, 2026. Court appearances for Medley and Kastner are expected in the coming days.