WASHINGTON — Here’s a new way to fight back attempts to spread fake news: file a police report.

That’s what Senator Chuck Schumer’s staff did on Tuesday in reporting to the Capitol Police the existence of a fraudulent document that described false allegations against the New York Democrat.

The document, which looks like a court filing, suggests that Mr. Schumer sexually harassed a staff member. The staff member who was named in the document as the plaintiff, and who no longer works for Mr. Schumer, told The New York Times on Wednesday that the harassment claims were “completely false.” The former staff member spoke on condition of anonymity.

Mr. Schumer’s spokesman, Matt House, said that the document was forged and that the allegations in it are false. Mr. Schumer is the top Democrat in the Senate.

“We have turned it over to the Capitol Police, and asked them to investigate and pursue criminal charges, because it is clear the law has been broken,” Mr. House said in a statement. “We believe the individual responsible for forging the document should be prosecuted to the fullest extent of the law to prevent other malicious actors from doing the same.”