LEWISTON – Lionel Guay, who was acquitted two months ago of groping a high school teenager who worked at his accounting firm, said Monday he is resigning as mayor of Maine’s second-largest city.

Guay, whose resignation takes effect Friday, told the Sun Journal of Lewiston that the past year has drained his family’s energy and health and that the time has come for him to step down.

“The mayor’s job is just a formality, really,” Guay said. “It’s not more important than my family, or the health of my family. That has to come first.”

Guay was charged a year ago with unlawful sexual touching and assault. Less than a week later, he was re-elected as mayor with 85 percent of the vote.

Guay’s term would have expired in January 2008, and the city charter bars him from seeking a third term.

Former Police Chief Larry Gilbert and City Councilor Normand Rousseau, who had already announced plans to run for mayor in 2007, said Monday they would seek to replace Guay when he resigns.

According to the city charter, Council President Renee Bernier will serve as temporary mayor until a special election can be held.

Guay said that despite his acquittal in September, the ordeal damaged him personally and hurt his family. He would not elaborate on the health problems but said they were stress-related.

“This decision is based on health reasons, and health reasons only,” Guay said. “We’ve talked to doctors, we’ve been prescribed medication and now we need to go off and get better. My wife and I are taking it all day by day.”