Hiram Monserrate is leaving no stone unturned in his effort to get back his state senate seat.

The Queens Democrat, who was expelled from the Legislature Tuesday night over a domestic violence conviction, plans to file a court challenge Thursday seeking the reversal of that decision as well an order to prevent a special election from taking place March 16.

“I was denied basic due process,” Monserrate said during a fiery floor speech before the 53-8 vote that booted him.

Monserrate’s attorney, Norman Siegel, said Wednesday he would file a petition in federal court as soon as it reopens after the snowstorm.

“The case raises substantial questions about what a constitutional democracy is about and one of those things is the right of the voters to choose their representatives,” Siegel said.

State Sen. Eric Schneiderman (D-Manhattan), who chaired a special committee that recommended either censure or expulsion, defended the process and was supported by women’s advocacy groups.

“The Senate did the right thing,” said Sonia Osorio, president of the New York chapter of NOW. “It would have been a slap in the face to New Yorkers to do anything less than expel him.”

Gov. David Paterson called a special election for March 16, and if it is held Monserrate said he will run. By Wednesday, the Senate, which is now in recess, had already removed Monserrate from its Web site.

Monserrate, a former police officer, was convicted of a misdemeanor for the December 2008 assault on his girlfriend but acquitted of felony charges. Senators are automatically removed if convicted of a felony but in Monserrate’s case, the law is unclear, said Richard Briffault, a law professor at Columbia and an expert on the state constitution.

The last state senator to be expelled was in 1781, and the state constitution was changed in 1821 to eliminate language explicitly granting senators the power to “purge” members.

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“It would be useful to have a court decision,” Briffault said.

Politically, sides have already been drawn. After Monserrate’s conviction last year, the Queens Democratic Party threw its support behind Assemb. Jose Peralta (D-Jackson Heights) to run for the disgraced senator’s seat. Peralta’s campaign did not return calls Wednesday seeking comment.