A new claim in a former hotel maid’s civil suit against Dominique Strauss-Kahn based on what his lawyers say is “an obscure, never-before-interpreted New York City law” should be dismissed as unconstitutionally vague, they argue in court papers.

Nafissatou Diallo, who claims Strauss-Kahn sexually assaulted her in a midtown Manhattan hotel in May 2011, filed civil charges in Bronx Supreme Court last August in Diallo v. Strauss-Kahn, 3070655/2011. The Manhattan District Attorney’s Office chose not to prosecute.

Diallo’s civil claims against Strauss-Kahn, the former head of the International Monetary Fund, include assault, battery, intentional infliction of emotional distress and false imprisonment. Diallo recently amended the complaint adding a fifth cause of action under the Victims of Gender-Motivated Violence Protection Act, NYC Administrative Code §8-901, et seq. (Read Diallo’s amended complaint.)

The city passed the local law in December 2000 to fill a void left after the U.S. Supreme Court, in United States v. Morrison, 529 U.S. 598 (2000), struck down a federal private right of action for victims of gender-motivated violence under the Violence Against Women Act of 1994. The high court concluded that the federal law could not be justified under the commerce or equal protection clauses of the Fourteenth Amendment.

To bring a claim under the city provision, Strauss-Kahn’s lawyers say, Diallo must prove the defendant committed a violent crime against her “due, at least in part, to an animus based on victim’s gender.”

A motion to dismiss before Bronx Justice Douglas McKeon (See Profile) filed this week by Strauss-Kahn’s attorney William Taylor, a partner at Zuckerman Spaeder, claims the statute’s provisions are ambiguous, especially the term “animus.” The City Council did not define it, nor has any New York court interpreted it, he said. (Read Strauss-Kahn’s motion to dismss.)

Animus-motivated conduct can be subjective and imprecise, Taylor writes, and “no ordinary person could decipher when conduct crosses the line from not being motivated by gender-based ‘animus’ to becoming actionable under the statute.”

“Does an overly promiscuous person possess ‘animus’ against members of the opposite sex because some might disapprove of such behavior?” the Strauss-Kahn motion asks. “Does an isolated off-color comment demonstrate ‘animus’ or must the plaintiff demonstrate a consistent pattern of objectively offensive statements?”

The lack of clear standards invites arbitrary enforcement of the act by plaintiffs, judges and juries, and it renders it unconstitutional under federal and state law, Taylor argues. The consequences are significant because the statute provides for punitive damages and attorney fees.

In Diallo’s amended complaint, she claims Strauss-Kahn referred to women in offensive terms, such as “luggage” and “gifts,” and the use of these words demonstrates that his conduct toward women and his assault on Diallo was “motivated by gender-animus and a misogynistic attitude.”

But Strauss-Kahn responds that whether the alleged comments demonstrate “‘animus’ toward women is a purely subjective assessment.”

Kenneth Thompson, Diallo’s lawyer and a founding partner of Thompson Wigdor, said in an interview that “this is another baseless motion by Dominique Strauss-Kahn, which we believe is designed to just delay the trial in this case.”

In May, McKeon rejected another motion to dismiss by Strauss-Kahn, who argued he had diplomatic immunity, citing his former post at the IMF.

Strauss-Kahn has filed counterclaims against Diallo for malicious prosecution and defamation, among other complaints. (Read Strauss-Kahn’s answer and counterclaims.)

In addition to the motion to dismiss, Strauss-Kahn’s attorneys this week requested the court to quash Diallo’s subpoena to Guidepost Solutions, a firm providing investigative and litigation support services to his legal team. (Read Strauss-Kahn’s motion to quash the subpoena.)

The subpoena seeks all communication between Guidepost Solutions and any third parties, except for attorneys, for services on behalf of Strauss-Kahn, according to court documents. It also asks for documents Guidepost received from and provided to third parties and any witness statements it obtained.

Strauss-Kahn argues that all the requested information is “protected from disclosure by the attorney work product doctrine” because Guidepost served as an agent for Zuckerman Spaeder and co-counsel.

Diallo’s lawyers also are seeking documents from the Manhattan district attorney, the New York Police Department and the Port Authority of New York and New Jersey, among others.

Thompson said he plans to oppose Strauss-Kahn’s motion on the subpoena, as his client is entitled to the documents. Diallo, who lives in the Bronx, is presently not working, he said.

“She’s waiting for her day in court. She wants to go to trial as soon as possible,” Thompson said.

Diallo is also represented by Thompson’s partner, Douglas Wigdor.

Taylor declined to comment.

Strauss-Kahn is also represented by Zuckerman Spaeder partners Shawn Naunton and Amit Mehta, and Rodman & Campbell partner Hugh Campbell.