INDIAN RIVER COUNTY — An Indian River County sheriff's deputy resigned in October upon notification she was under investigation for an "inappropriate" relationship with an inmate, according to an internal affairs report.

Investigators found former Deputy Whitney Marion, 27, of Okeechobee, had phone sex and "highly suspect" contact with a man at the Indian River County Jail over the course of a week in mid-October, the memo said.

The inmate involved was identified as Michael Gonzalez, 28, of Ruskin. Jail records showed he is serving a 364-day sentence for a probation violation in a driving-while-license-suspended case.

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Sheriff's personnel reviewed 12 phone calls Gonzalez placed from the jail to Marion's phone, which included explicit discussions of a variety of sexual activities, according to the memo.

Jail surveillance also revealed two instances in which the pair disappeared into storage areas for one or two minutes, contact officials described in the memo as "highly suspect, especially when considered in light of the phone conversations."

Marion had been with the agency five months when the allegations surfaced. She resigned Oct. 19.

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