Immigration and Customs Enforcement agents are dropping terrorism investigations or steering them in other directions because they don’t want to work with FBI agents, according to a joint report by the inspectors general of the Department of Homeland Security and the Department of Justice.

ICE agents told the investigators they do not want to work with the FBI because of a variety of negative perceptions — mistaken perceptions, according to the IGs’ report — about cooperating with the bureau.

Agents told inspectors that “they or other agents drop leads that appear to have a terrorism nexus, or choose to ignore a terrorism nexus and select violations unrelated to terrorism, in order to continue [a] case without FBI involvement,” says the report, which was requested by Sen. Charles E. Grassley, R-Iowa, and released by his office this week.

In May 2003, DHS and DOJ signed a memorandum of agreement to coordinate the investigation of terrorist financing cases by ICE and the FBI. The agreement affirms the FBI is the lead agency on terrorist financing cases and produced a system for identifying and transferring ICE cases that have a connection to terrorism to FBI-led joint terrorism task forces (JTTF).

But “highly negative views and significant misinformation” about the JTTFs’ handling of terrorist financing cases under the agreement may be causing ICE agents to drop terrorism-related leads or cases, the report finds. “We encountered suspicion and hostility from ICE agents towards the [agreement to coordinate], but their claims about the way the JTTFs operate were unfounded.”

Among the allegations by ICE agents that the investigators said were unfounded were charges that ICE did not receive a share of the recognition for successful cases, and that the FBI took cases away from ICE agents.

Investigators said they were “extremely troubled that ICE agents would say that their agents declined to undertake a case of potential national security significance for such petty reasons,” the report says, adding that it has no direct evidence of specific cases ignored for such reasons.

The inspectors recommend both ICE and FBI agents’ understanding of the agreement between the two agencies be increased to correct misunderstandings between the two agencies.

“I hate to think how much our law enforcement agencies could be missing because of petty turf battles,” Grassley said. “That kind of institutional vanity should have been history on Sept. 12, 2001.”

This story originally appeared in CQ Homeland Security.