The city is investigating whether a preservationist pretended to speak on behalf of Borough President Scott Stringer at a public meeting of the Landmarks Preservation Committee in October.

A volunteer preservationist, Virginia Parkhouse, read from a letter that Mr. Stringer sent to the Landmarks Commission and a local community board supporting the designation of two former stables on the Upper West Side. Neighbors and preservationists were fighting to preserve the Dakota Stables and the New York Cab Company Stables, both near Amsterdam Avenue, which were threatened with residential development. The Cab Company building was eventually designated as a landmark by the commission.

In May, the city’s department of investigations served Ms. Parkhouse with a subpoena commanding her to testify and prove that she was not trying to falsely represent herself to the Landmarks Commission as an official representative of Mr. Stringer.

Yesterday, Ms. Parkhouse filed a motion in Manhattan’s State Supreme Court asking a judge to throw out the city’s subpoena.

Ms. Parkhouse’s motion claims that the subpoena “constitutes an abuse of power and official harassment of Ms. Parkhouse,” and is “a plain and flagrant deprivation of her and her civil rights.”

A letter from the department of investigation to Ms. Parkhouse’s lawyer, also included in the court papers, defends the investigation.

“The public…has a right to know the accurate views of its elected officials with respect to matters of public concern and no individual has the right to attempt to add credence to her own particular viewpoint by falsely representing that her view is in fact the view of an elected official.

A spokeswoman for the department, Diane Struzzi, had no comment yesterday.