ALBANY -- The state Senate voted 53-8 Tuesday to expel a Queens senator for conduct unbecoming his office in connection with a misdemeanor conviction on an assault charge.

Freshman Sen. Hiram Monserrate, a Democrat, said the Senate had no authority to remove him from office and acted unconstitutionally. He said the Senate's decision disenfranchises the voters who elected and vowed to fight the vote in federal court.

The domestic-violence incident the senator was convicted on took place before he took office.

"I think it's the height of arrogance for someone who has never pulled a lever in my community, never saw a narcotics deal on Roosevelt Avenue and never saw the lack of services that my community receives, to think that today, they have more power than the constituent voters who sent me here to represent them," Monserrate said.

Democratic senators had met privately for hours to debate what action they would take. One option was censure of Monserrate, but they did not introduce that resolution.

Monserrate apologized to his colleagues for "all the pain and upset" that occurred as a result of his actions.

Had Monserrate been convicted of a felony, he would have automatically lost his Senate seat. A Senate committee that investigated Monserrate's actions recommended several weeks ago that the senator be censured or expelled.

The eight no votes were Democrats from New York City. Twenty-nine Republicans voted for the resolution. The 30th Republican, Sen. Thomas Morahan of New City, Rockland County, was excused due to illness.

Without Monserrate, Democrats hold just a 31-30 edge over Republicans. Last year, Democrats took control of the Senate for the first time in decades. All lawmakers are up for reelection this fall, and Republicans are seeking to take back control of the Senate.

Monserrate was one of two Democrats involved in a Republican Senate coup last June and July. He and now-Senate Majority Leader Pedro Espada, D-Bronx, joined the GOP to take control of the Senate. Ultimately, both Democrats returned to their conference and Democrats regained control of the house.

Anger over Monserrate and Espada's role in the coup still lingers among Senate Democrats.

Sen. Eric Schneiderman, D-Manhattan, said the expulsion of a senator "is a rare action that ought to be considered only in the most egregious of circumstances."

Schneiderman chaired a bipartisan Senate committee that investigated Monserrate's actions.

Senate Democratic Conference Leader John Sampson, D-Brooklyn, said he voted not to remove Monserrate because the appeal of his misdemeanor conviction is still pending in state Supreme Court.

Marcia Pappas, president of the National Organization for Women in New York, called the vote a victory for the women of the state. The group has said anything other than expulsion would be unacceptable.

"Any form of violence against women is not acceptable. We hope that this serves as a wake-up call to all lawmakers. Whether you are a candidate or a sitting elected official, if you are violent towards another person, you are not fit to hold office," Pappas said in a statement.

Sen. Stephen Saland, R-Poughkeepsie, said the vote demonstrates the Legislature's "zero tolerance position toward domestic violence" and said Monserrate's action compromised the integrity of the office of senator.