Joel Palmer Watts, 27, is accused of demanding $10,000 from state Sen. Paul Stanley, R-Germantown, in exchange for explicit photos he found that were taken at Stanley's Nashville apartment, the Memphis Commercial Appeal reported Wednesday.
Watts was arrested in a sting operation after Stanley contacted the Tennessee Bureau of Investigation about the blackmail attempt.
He told police the legislative intern was his girlfriend.
Stanley, who is married and the father of two children, released a prepared statement about the matter.
"Unfortunately, I am the victim and a witness to a crime in an ongoing investigation," the statement said, adding that authorities had advised him not to comment further.