A former state legislator pleaded guilty Monday to immigration fraud for his role in a scheme to allow women from Russia and Ukraine to stay in the U.S. illegally, and arranging a sham green card wedding.

Adam Mack, 39, of Portland, faces up to 10 years in federal prison and a $250,000 fine on two charges of aiding and abetting visa fraud and up to five years and a $250,000 fine on charges of aiding and abetting marriage fraud and making false statements to a government agency, according to U.S. Attorney Thomas Delahanty II’s office.

Mack, a Republican who represented Standish from 1998 to 2000, previously was convicted of misusing federal funds in connection with a property management company he owned. He was ordered to serve six months in prison and repay $384,000 in restitution to the federal government. That fine contributed to his filing in December for bankruptcy protection.

Mack now is on supervised release in connection with the earlier conviction but the immigration fraud predated his other conviction so he was not charged with violating conditions of his release.

According to documents filed in U.S. District Court in Portland, Mack filed paperwork between 2009 and 2011 with the federal government saying a woman from Russia and another from Ukraine worked for him when they didn’t. The documents were used to obtain visas for the women allowing them to remain and work in this country.

Mack also helped arrange a fake marriage in Cape Elizabeth between one of the women, Mariia Shevchenko, and Christopher Segal, who was paid by Shevchenko. The court papers do not say how much Segal was to receive, though he did receive one installment of $800.

Mack helped the couple prepare for their interview with U.S. Citizenship and Immigration Services, but during the interview, Segal confessed that the wedding was a sham, according to court papers filed by Assistant U.S. Attorney Darcie McElwee.

Authorities executed a search warrant on Mack’s home on May 22, 2014, and found evidence of the fraud on his home computers.

Court records do not indicate what gain Mack received from the arrangement.

A telephone message left at Mack’s listed telephone number in Standish was not returned.

In his two terms in the Legislature, Mack sponsored several pieces of legislation, including replacing the graduated income tax with a flat tax, eliminating funding for the Family Planning Association of Maine and prohibiting felons from voting, all of them unsuccessful. He also sponsored a bill to allow a referendum on Frye Island’s secession from Standish, which passed the Legislature and won voter approval.

Mack will be sentenced after a presentence investigation report is prepared by the U.S. Probation Office.

The investigation was conducted by U.S. Immigration and Customs Enforcement’s Homeland Security Investigations and the U.S. Department of State, Bureau of Diplomatic Security.