Two former Peace Corps volunteers filed a lawsuit against the agency in federal court this week, demanding the release of data from annual surveys of volunteers.

Charles Ludlam and Paula Hirschoff, spouses who describe themselves as “leading advocates” for reform within the Peace Corps, say their requests for the data under the Freedom of Information Act were blocked by the agency’s staff.

The annual survey, broken down by the 77 countries where volunteers serve, provide prospective volunteers with vital information on safety and security, staffing, training and the effectiveness of programs, the lawsuit says.

“If the Peace Corps does not provide relevant information that enables the applicant to assess the quality of the program, the applicant should consider carefully whether or not to accept the invitation to serve,” the complaint says. “Applicants are being asked to spend two years of their lives as volunteers, so the least the agency can do is provide full transparency about the Peace Corps and the management and effectiveness of its programs.”

The Peace Corps has come under fire from Congress in recent months for its handling of sexual assaults against volunteers overseas.

A spokeswoman for the organization declined to comment on the lawsuit until the Justice Department, which represents federal agencies, reviews it.

Ludlam and Hirschoff cite the 2009 murder of Kate Puzey, a volunteer in Benin, as proof of the public interest in having the data released.

The plaintiffs allege that a Peace Corps official denied their request for country-by-country data on the grounds that it would reveal personal information about volunteers. The agency also said it would charge thousands of dollars to produce the documents. The lawsuit says the data had already been compiled for internal use.

Eventually, the couple obtained a country-by-country breakdown for 2008 through unofficial channels. It was posted on peacecorpswiki.org, a Web site devoted to providing information for volunteers. The lawsuit seeks data by country for 2009 and 2010.

Hirschoff and Ludlam served in the Peace Corps from 1968 to 1970 and again from 2005 to 2007.