(SHELBY TOWNSHIP) -- A man suspected of being mentally ill has been charged with threatening U.S. Rep. Candice Miller unless she paid $1 million. A criminal complaint unsealed this week accuses Robby Harris of mailing a threatening letter to the office of the Macomb County Republican. Miller was not harmed. Harris was identified by a woman who lives in the same Pontiac apartment complex. A court filing says the woman told the FBI that Harris had listed her address on letters to other public officials, schools, even the White House. FBI agents talked to Harris and his mother and were shown the same paper, envelopes and stamps used to send the other letters. He was in custody Thursday awaiting a court hearing Friday. Harris asked for a court-appointed lawyer. Miller serves Michigan's 10th Congressional District, which includes northern Macomb County, a portion of Tuscola County, and St. Clair, Sanilac, Huron and Lapeer counties.