By Matt Davis, The Lens staff writer

Sheriff Marlin Gusman has no hard evidence to back his recent claim that New Orleans needs a jail that would hold 3,200 people, even after an expert hired by the city said a 1,500-bed jail would be sufficient.

The claim was based on “institutional knowledge,” said an attorney for Gusman in a response Friday to a public records request filed by Marjorie Esman, Executive Director of the American Civil Liberties Union of Louisiana.

Gusman’s claim, made on Dec. 7, contradicted work done by consultant James Austin, who was hired by Mayor Mitch Landrieu’s Criminal Justice Working Group. The group was formed by Landrieu to recommend an optimal size for the city’s prison and jail complex by Nov. 22, but it has yet to do so.

Esman sought studies or data on which Gusman could base the 3,200-bed claim. But Gusman attorney T. Allen Usry wrote that none existed.

“The sheriff’s calculation of the future prisoner population was based on institutional knowledge and experience in the operation of the Orleans Parish Jail Facilities in this City,” Usry wrote. “This basis was not reduced to a written report or formal study. Nor were any particular data compilations used to formulate this calculation.”

Esman said she was not surprised by the response.

“It’s arrogant for the sheriff to suggest that he knows better than a nationally recognized expert, when his response shows he has no basis for the continued insistence on more beds,” Esman said. “His suggestion that it’s based on institutional knowledge is the same thing as him saying, essentially, that he’s making it up.”

The next meeting of the working group is Friday at 2 p.m., in the eighth-floor conference room at City Hall.