Last year, following the disclosure that 123,000 Thrift Savings Plan accounts had been hacked, the Federal Retirement Thrift Investment Board launched a wide-ranging assessment of its computer system security. That “Tiger Team” task force review is now complete, but the board isn’t making the findings public. Instead, the agency is withholding the entire report on the grounds that disclosure “could reasonably be expected to risk circumvention of the law,”  Amanda Haas, a Freedom of Information Act officer with the board, said in a response today to Federal Times’ FOIA request. Haas did not immediately reply to a request for more information…