A man charged with bigamy after his girlfriend's sister saw him profiled on the "Dr. Phil" television show pleaded guilty Thursday.

Charles Edward Hicks, 62, has been married seven times in 40 years. He was charged with bigamy involving his fifth and sixth wives.

He is to be sentenced May 8 and faces as many as 10 years in prison.

Hicks married Julie Flint in 1997 while married to Rose Marie Sewell, prosecutor Derek Wagner said.

Wife No. 7, Sandra Goldin Hicks, tried unsuccessfully last year to have Hicks prosecuted for his marriage to her. But because the sixth marriage wasn't legal and he already had divorced the fifth wife by the time he married Sandra Hicks, he did not commit a crime.

Hicks was profiled on "Dr. Phil" in December, when two women who had learned they both were married to Hicks went on the show. A viewer recognized Hicks as her sister's boyfriend and called authorities.