WASHINGTON (CNN) -- Staffers in the voting rights section of the U.S. Justice Department -- during both the Bush and Obama administrations -- took political potshots at each other and often displayed a lack of professionalism, according to a report issued Tuesday.

The department's inspector general found camps within that office battled over priorities and cases for most of the past decade.

But the report found that there was "insufficient support for a conclusion that Civil Rights Division leadership in either the prior or current administration improperly refused to enforce the voting rights laws on behalf of any particular group of voters or that either administration used the enforcement of laws to seek improper partisan advantage."

The report covers a series of controversies during the years 2001 to 2011, when first George W. Bush, and then Barack Obama controlled the Justice Department.

The voting rights pot boiled over on November 4, 2008, when two members of the New Black Panther Party stood outside a polling station in Philadelphia dressed in boots and berets and carrying a nightstick. Civil charges for attempted intimidation were filed, but then dropped against three of four defendants.

Republican lawmakers demanded an investigation, and the inspector general agreed to look at the activities of employees within the voting rights section.

The report is unlikely to satisfy partisans of either party.

It is expected to be a prime topic Thursday when a House Appropriations subcommittee questions Inspector General Michael Horowitz.

The subcommittee chairman, Rep. Frank Wolf, R-Virginia, has been one of the driving forces pushing the investigation. Wolf is among those questioning the dropping of charges against the Black Panthers.

The "unprofessional" behavior cited by the inspector general stemmed largely from many e-mails which were posted on outside websites. Employees of the voting rights section engaged in general sniping against co-workers who did not share their political views.

In a reference to Republicans, a "good ethical Republican is a seeming oxymoron," one employee said. The report also said these 2007 e-mails "contained heated political and even racist commentary." In one such case, one official said administration officials or voting section managers were "bigoted against blacks or other racial minorities." One commenter used a racially derogatory term in describing a manager's attitude toward blacks.

Assistant Attorney General Thomas E. Perez, who heads the department's civil rights division, said he agreed with most of the recommendations made by the inspector general. "We recognize that although significant progress has been made, additional work remains," Perez wrote.

Perez will be nominated as the next labor secretary, a Democratic source told CNN over the weekend. If approved, he'd take the position recently held by Hilda L. Solis, a former congresswoman who resigned in January.