Law enforcement officials in Illinois said Friday that they would not bring criminal charges against the famed Metropolitan Opera conductor James Levine, noting that the man accusing Mr. Levine of sexual abuse there three decades ago had been 16 at the time — which was then the age of consent.

“As such, even if it were possible to establish the alleged acts took place, they do not constitute a criminal offense under the applicable law,” the Lake Forest Police Department said in a statement.

The police had been investigating a complaint made last year by Ashok Pai, 48, who grew up in Illinois and said that he was sexually abused there as a teenager by Mr. Levine, who was then the music director of the Ravinia Festival, near Lake Forest. Mr. Pai accused Mr. Levine of lying naked with him in bed and touching his penis while at a hotel near the festival in 1986, when Mr. Pai was 16, beginning years of sexual contact.

Mr. Levine, 74, was suspended on Sunday from the Metropolitan Opera, his artistic home of more than 40 years, after three men — including Mr. Pai — came forward with accusations that he sexually abused them decades ago, when the men were teenagers or students of his. (A fourth man came forward on Monday with a similar accusation.) Friends and relatives of the accusers said in interviews that the men had either complained of Mr. Levine’s abuse near the time it happened or in the years since.