By Missy Ryan
WASHINGTON (Reuters) - The United States cannot consistently ensure that former Guantanamo Bay detainees will not engage in militant activity once they are released from the military prison or transferred to a third country, a new congressional report found on Thursday.
The report from the Oversight and Investigations Subcommittee of the House Armed Services Committee examined efforts by the Obama and Bush administrations to move detainees from the military prison in Cuba, which has held 779 prisoners since it opened in the wake of the September 11, 2001, attacks.
According to an unclassified version of the report obtained by Reuters, some 27 percent of the 600 former detainees who were moved out of Guantanamo had been "confirmed or suspected to be presently or previously engaged in terrorist activities."
Over the years, detainees have been transferred to countries such as Afghanistan, Saudi Arabia, Pakistan, Yemen, Spain and Denmark.
"Evaluating detainees and ensuring that their cases were handled appropriately by receiving countries was, and remains, a challenge," the report said.
The report recommended that the Obama administration produce a study on Guantanamo detainees' recidivism and provide Congress with an analysis of how well countries that have or might receive detainees can manage such individuals.
"There needs to be a lot more work done on the issue of re-engagement before we can safely and securely make (sure) these transfer arrangements are sufficient," a House staff member said on condition of anonymity.
The report is one more indication of the struggle that President Barack Obama has faced in his efforts to shut down the controversial military prison, which has been a flashpoint for worldwide criticism of the U.S. response to terrorism.
It also comes as the White House considers transferring five senior Taliban officials to Qatar as part of its efforts to broker a peace deal in Afghanistan, another idea that has already generated significant pushback from Congress.
No detainees have been transferred out of Guantanamo since January 2011, in large part because of congressional restrictions. Congress has also voted repeatedly to limit transfer of detainees to the United States for trial.
Late last year, lawmakers also imposed additional transfer restrictions in a defense authorization bill.
While the report, headed by the Republican subcommittee chair, Robert Wittman, was originally conceived of as a bipartisan effort, committee Democrats issued a lengthy dissent that disagreed with much of its findings.
They accused Republicans of fear-mongering for political gain, ahead of November's election that Democrat Obama hopes will give him a second term.
"The Armed Services Committee is not accustomed, and should not lower itself, to wearing blinders, dumbing down information, and hinting darkly, all in order to attempt a partisan advantage," Representative Jim Cooper, the top Democrat on the subcommittee, said in a statement.
Democrats also disputed the report's assertion that more than a quarter of former Guantanamo prisoners were possible militants, saying the true figure was far lower.
Last week, the Defense Department said that as of December 2010, 14 percent of the nearly 600 detainees who had left Guantanamo were confirmed of later taking part in militant activity, and 12 percent were suspected of such activity.
Democrats also said the report failed to consider adequately the national security risks the United States caused by keeping detainees at Guantanamo without trial.
(Additional reporting by Jane Sutton; Editing by Peter Cooney)