A federal judge in Newark has turned back the American Civil Liberties Union’s request for information about the FBI’s allegedly unconstitutional use of racial and ethnic “mapping” under the pretext of policing national security.

U.S. District Judge Esther Salas held Monday in ACLU-NJ v. Department of Justice, 11-cv-2553, that the bureau conducted adequate records searches and satisfactorily explained its decisions to withhold some of the documents.

“The fact that other documents possibly responsive to the request exist but were not uncovered by an agency’s search is immaterial to the adequacy of that search,” Salas wrote.

The ACLU-NJ made a Freedom of Information Act request on July 27, 2010, to Federal Bureau of Investigation headquarters, the Newark field office and satellite offices in Hamilton, Northfield, Red Bank, Somerset and Woodland Park, seeking documents related to “use of race and ethnicity to conduct assessments and investigations in local communities in New Jersey.”

In particular, the ACLU-NJ sought information gleaned by use of the FBI’s Domestic Investigation and Operations Guide, which allows agents to collect, analyze and map racial and ethnic data.

It was one of at least 34 FOIA requests filed that year by the ACLU and its affiliates, spurred by concerns that the FBI exploited a loophole established in a 2003 Department of Justice directive that allows racial and ethnic profiling in connection with national security or “border integrity” investigations.

In New Jersey, the FBI has used the presence of MS-13, a violent Salvadoran gang, to justify broad investigations of Central American and other Hispanic communities, the ACLU-NJ alleged.

In response to the request, the FBI searched its central records system using various terms such as “racial and ethnic community demographics,” which yielded no results.

The bureau then instructed the Directorate of Intelligence, Office of the General Counsel and the New Jersey offices to conduct searches of electronic and paper records for documents dating back several years, including information related to ethnic communities and their connection or likely connection to criminal or terrorist groups.

The searches yielded 782 pages, 298 of which were handed over on Dec. 22, 2010. The records, some of them redacted, consisted of training materials related to the Domestic Intelligence and Operations Guide. The bureau later released about 20 additional pages. The remaining 470 pages were withheld under various FOIA exemptions.

The ACLU-NJ filed suit on May 4, 2011, challenging the adequacy of the search, the withholding of the documents and the affidavits explaining the bureau’s decisions.

On Monday, Salas entered summary judgment for the government and denied the ACLU-NJ’s motion.

She found that affidavits from David Hardy, chief of the FBI’s Records/Information Dissemination Section, sufficiently explained how the bureau determined the locations and the nature of the search, noting that the FBI directed personnel to retrieve all electronic, paper, audio and video records.

Salas dispatched the ACLU-NJ’s contention that the FBI failed to release electronic communications “likely” created or received in the Newark field office, saying she “need only consider whether the search was adequate, not whether certain documents exist.”

Any exclusions based on “highly sensitive” material were justified, she added. And “description of operations, including threats and vulnerabilities to Newark area operation logically falls into” the FOIA exemption for documents related to national security.

The department also justified exemptions used to withhold records that purportedly would interfere with ongoing proceedings, or current or prospective investigations; constitute an unwarranted invasion of agents’ personal privacy; expose the identity of a confidential source; or reveal law enforcement or prosecutorial techniques and procedures.

“While the public may know that some of these techniques and procedures exist, it does not know the manner in which the FBI uses them,” Salas noted.

Hardy also sufficiently explained why releasable material in some withheld documents was not segregable from exempt material, Salas said.

Nusrat Choudhury, of the ACLU’s National Security Project, says there will be an appeal. “Our main disagreement with the district court is that the FBI just didn’t meet its burden,” she says.

The FBI “withheld even publicly available info,” some of which was made available in response to other FOIA requests elsewhere in the country, Choudhury says.

She adds that the FBI “has provided little information” in response to all 34 of the requests. Aside from New Jersey, the ACLU is litigating in Michigan and California.

Deanna Lynn Durrett of the Justice Department’s Civil Division, who represented the government, did not return a call. Department spokesman Charles Miller declines comment.