It’s one of the U.S. Border Patrol’s most controversial practices: shooting at migrants and suspected drug runners who throw rocks and other objects at agents. Many law enforcement experts say the best option is to take cover or move elsewhere, rather than use lethal force.

A law enforcement think tank — hired last year by parent agency U.S. Customs and Border Protection to review the Border Patrol’s practices — recommended restraint when agents encounter rock throwers who don’t pose an imminent threat of serious injury or death.

But when the Department of Homeland Security’s inspector general released a report in September on the Border Patrol’s use of force, officials blacked out that call for holding back in such incidents, among other recommendations, according to an uncensored copy reviewed by the Center for Investigative Reporting.

The redacted report highlights how the Department of Homeland Security has attempted to mute the debate surrounding a spate of agent-involved shootings that have killed more than 20 people since 2010, critics say.

Josiah Heyman, an anthropology professor at the University of Texas at El Paso who co-wrote a recent report on the Border Patrol that focused on migrant abuse, said the agency has a long tradition of resisting greater transparency, which has limited public discussion about issues such as the appropriate use of force.

“Accountability is absolutely fundamental in this whole story,” he said.

William Hillburg, a spokesman for the inspector general’s office, declined an interview request. He wrote in an e-mail that the report was “redacted due to deliberative material.”

Congress asked the inspector general to review the agency’s training and policies on the use of force in spring 2012. The inspector general included material from a 2013 report that Customs and Border Protection commissioned from the Police Executive Research Forum, a Washington-based law enforcement think tank.

Agency officials ordered the outside review after a rash of fatal shootings, including the October 2012 death of Border Patrol Agent Nicholas Ivie, who was killed after mistakenly exchanging gunfire with other agents while on patrol in Arizona.

The think tank report, portions of which were shared with The Washington Post and CIR, recommended that Customs and Border Protection “train agents to de-escalate these encounters by taking cover, moving out of range and/or using less lethal weapons. Agents should not place themselves in positions where they have no alternatives to using deadly force.”

In a written statement provided to The Post and CIR, agency spokeswoman Melanie Roe said the agency has begun implementing the vast majority of the recommendations, but the report remains for internal use.

R. Gil Kerlikowske, the nominee for Customs and Border Protection commissioner, signaled during a Senate hearing earlier this month that if confirmed, he would push for more transparency with the agency’s use-of-force policies.

“If you don’t have the trust and the cooperation of the people you serve and they don’t understand or they’re not knowledgeable of your policies, it makes that trust and cooperation very difficult,” he said.

The Border Patrol has resisted calls to limit deadly force against rock throwers, who often try to distract or retaliate against agents along the Southwest U.S. border. Agents say that when migrants or suspected drug runners hurl rocks at them, it could be lethal.

Such confrontations have ended in fatal shootings, including the killing of minors across the international boundary from Arizona and Texas into Mexico. No agents have been killed by thrown rocks.

Michael J. Fisher, chief of the U.S. Border Patrol, rejected two of the think tank’s main recommendations in an Associated Press interview published in November. He told the AP that the agency did not agree with restrictions on using deadly force against rock throwers and potential assailants in moving vehicles.

Human rights groups have questioned the agency’s stance on shootings, and pushed the agency to publicly release its use-of-force policy. Customs and Border Protection released a redacted copy of the handbook in response to a federal Freedom of Information Act request.

CIR obtained a complete copy of the 2010 policy handbook, the most recent version. The think tank recommendation not to shoot at people or moving vehicles if they don’t pose an imminent threat of death or serious physical injury to agents or others closely follows the agency’s policy on the use of deadly force.

For instance, according to the agency’s Use of Force Policy Handbook, an agent or officer may use deadly force against the driver or other occupant of a moving vehicle if he or she has a reasonable belief that the subject of such force poses an imminent danger of death or serious physical injury and “the hazard of an uncontrolled conveyance has been taken into consideration before firing.”

The inspector general also blacked out the number of recommendations made by the think tank — 55 — and even redacted information about agency actions that the review’s authors applauded, such as the use of a computer-generated mapping program that helps Customs and Border Protection study use-of-force incidents.

The National Border Patrol Council, the union representing more than 17,000 agents, echoed Fisher’s rejection of the recommendations to stop shooting at rock throwers and moving vehicles.

In an interview, Shawn Moran, a national vice president and spokesman for the agents’ union, said that the Border Patrol’s strategy to pressure unauthorized border crossers by placing agents close to the layered border fence contributes significantly to rock-throwing incidents and the agents’ response with force.

“When our agents are stuck between the primary and secondary fence, a lot of times, they don’t have anywhere to go” to take cover, he said. “I think rockings would dramatically decrease” if the agency jettisoned the strategy.

This report was produced by the Center for Investigative Reporting, a nonprofit, independent newsroom based in Berkeley, Calif. For more, visit