Advocates for the disabled argue that the pending changes will have the effect of denying funds to thousands of people with severe mental and physical handicaps.
The changes do not require congressional approval.
One set of proposed new rules would save Social Security an estimated $6 billion over the next decade by raising the ages at which applicants for disability are subjected to less stringent eligibility criteria.
An age-based system has been in place since 1978, on the theory that it is harder for older people to find a job than for younger workers after a devastating accident or illness.
The other changes would revise the slow, cumbersome, multistep process by which applications for disability status have been resolved. Among disability advocates, these prospective changes have generated considerable opposition.
"While justice delayed can be justice denied, justice expedited can also result in justice denied," Marty Ford, cochair of the Social Security Task Force of the Consortium of Citizens With Disabilities said in congressional testimony.
In announcing the proposed new rules last year, Social Security Administrator Jo Anne B. Barnhart said she was guided by questions President Bush had put to her, including why it took so long to get a final disability decision and why obviously disabled people could not get a near-immediate decision.
"My goal was to address the President's questions and ensure that we make the correct decision as early in the process as possible," Barnhart said. "The regulation we are proposing would do just that."
Under current rules, the process has five steps. The initial determination is made in a state office by officials who never actually see the applicant. Then comes reconsideration, a hearing before an administrative law judge, review by an Appeals Council, and finally, access to the federal courts.
