Democratic state Sen. James Marzilli Jr. was arraigned Wednesday in Lowell, Mass. He pleaded not guilty to a list of charges that included annoying and accosting a person of the opposite sex and attempting to commit indecent assault and battery, the Boston Globe reported Thursday.

Marzilli was arrested last month after he allegedly groped four women and then led police on a foot chase. He also allegedly groped a woman in his home town, Arlington, in a separate incident.

After the hearing, his lawyer, Terrence Kennedy, said his client has been diagnosed as bipolar.

"A lot of people have bipolar disorder, and they don't hurt others," said Wendy Murphy, a lawyer representing the Arlington woman. "And they certainly don't assault women in a sexual way, especially in such a prolific sexual way in the course of several years. If he thinks that's somehow justification for his behavior, he's wrong."

Marzilli, who won a special election to the state Senate last year after years in the General Assembly, has already announced he will not seek re-election this year.