The federal government is investigating how D.C. public schools respond to reports of sexual violence and what they are doing to prevent such incidents, a senior U.S. education official said Monday.

The inquiry comes after an allegation of a rape last fall at Dunbar High School in Northwest Washington. Russlynn H. Ali, assistant education secretary for civil rights, said that even though criminal charges were eventually dropped in that case, the incident raised broader questions that warrant federal review.

“Now it’s about what is the environment in your school and in your district,” Ali said. “Do girls and young women feel safe? What are the procedures if this were to happen again? What would be the immediate response?”

Ali said federal officials were seeking to help D.C. Acting Schools Chancellor Kaya Henderson and other school chiefs across the country who might face similar challenges. “They need to make sure they have a culture that is safe for all of their students,” Ali said.

D.C. schools spokeswoman Safiya Simmons said the U.S. Education Department “is working to introduce new guidance to help schools, colleges and universities understand their civil rights obligations to better prevent and respond to sexual assault.”

Ali added, “The District is cooperating fully, and we’re working to resolve the matter.”

The disclosure comes as the Obama administration is pushing colleges and schools to take steps to prevent sexual violence on campuses through expanded enforcement of civil rights laws.

Vice President Biden announced the initiative Monday at the University of New Hampshire, making public a 19-page letter of regulatory guidance to schools from the Education Department. The letter specifies for the first time that rape, sexual assault and sexual battery should be considered not only crimes but also instances of discrimination covered by the federal rules that bar sexual harassment.

The administration’s letter cites data showing that nearly 3,300 forcible sex offenses were reported on college campuses in 2009. In addition, there were reports of 800 rapes and attempted rapes and 3,800 incidents of sexual battery at public high schools in 2007-08. The letter did not cite any trends in that data.

The administration says schools that receive federal funding are obligated to guard against sexual violence and to act swiftly on complaints.

Education Secretary Arne Duncan told reporters in a conference call that schools should not wait until the end of criminal investigations to review whether they have a civil rights problem when sexual violence is reported.

“They can, and they should, start right away,” he said, adding: “Our primary goal is prevention through education. Information is always to the best tool to combat sexual violence.”