Frank Dunbaugh, a board member of the Maryland Justice Policy Institute, said he feared the incident might accelerate a national trend away from treatment.
"Over the years, the politics have changed a lot. Now, we have the idea that everybody should be held responsible for every act," he said. "An incident like that is going to bring more political pressure to bear that everybody ought to be treated in the harshest manner."
Created in the 1950s as a model approach to rehabilitation, the Patuxent Institution was built to treat violent criminals with severe mental problems.
The Jessup, Md., facility still deals with prisoners with psychiatric problems, but the freedoms granted have been severely restricted and the conditions under which inmates are eligible for the program have been narrowed, officials said.
Inmates receive intensive counseling from psychiatrists, psychologists and social workers.
Leonard A. Sipes Jr., a spokesman for the Maryland Department of Public Safety and Correctional Services, said murderers sentenced after 1989 are not eligible for privileges like unsupervised leave.
Sipes said Patuxent treated offenders who were the worst of the worst.
"It was the idea that if we can cure these inmates, we can cure anyone. It was a failed experiment," he said.
Although the state has moved to curtail Patuxent inmates' freedoms, Sipes said court decisions prevent them from rescinding privileges to compliant inmates who were sentenced before 1989.
In the wake of the Carpenter incident, state officials have suspended all leave and work-release programs and have ordered a review of the programs.
But Dunbaugh, who edits the newsletter Just Line, said one incident should not jeopardize the entire system.
Eric E. Sterling, executive director of the Criminal Justice Policy Foundation, said maintaining a system of privileges is vital to prison management.
"If you have no carrots in your system, managing your institution becomes extremely difficult," he said.
Rather than condemn the entire system, prison officials should focus on the details of the Carpenter case, Sterling said.
"Was there a breakdown in getting accurate information about the inmate? Did authorities make the right conclusion?" he said.
Even freedoms such as weekend furloughs might be reasonable in some cases, Sterling said. Revoking all privileges is an "overreaction," he said, adding that officials and the public should recognize that it is impossible to eliminate risk.
To those who question why officials should even take a chance, Sterling said it is important to try to rehabilitate inmates who one day will return to society. This is true even for some violent offenders.
Carpenter, himself, became eligible for parole in 1993.