When Dr. Robert E. Ferrell's attorney negotiated his guilty plea in federal court down to a misdemeanor, with only a minimal fine and unsupervised probation, it was a huge relief.

Sure, Efrem M. Grail wanted to take the case to trial -- more than any he's had in the last 10 years, he said, because he felt the charges never should have been filed in the first place.

But his client was not well enough to travel to Buffalo, N.Y., for the litany of pretrial hearings that would occur.

Instead, Dr. Ferrell, a genetics researcher at the University of Pittsburgh, admitted to mailing an injurious material.

But his co-defendant, a friend and former art professor at Carnegie Mellon University, who faced the same charges, continued to fight.

And in April, Steven Kurtz beat the charges completely when a federal judge dismissed the case saying the indictment was insufficient and did not cite an actual crime.

"I suppose it will always stick in my gut that I'm the lawyer that pled the client to a misdemeanor in the case that got dismissed," Mr. Grail said.

Critics of the U.S. attorney's office in Buffalo have argued since the case was initially filed in June 2004 that the charges were unwarranted and motivated by a government trying to foster public fear.

Both men were charged with fraud after Dr. Ferrell ordered two biological materials for Mr. Kurtz to use in an art project. They were initially sent to Pitt, and then Dr. Ferrell forwarded them to Mr. Kurtz in Buffalo, where he had moved.

Though health officials said the materials posed a low risk of infection, the case quickly was linked to bioterrorism and an indictment was brought.

During the years that the case dragged on, supporters of the two men held rallies and fund-raisers to pay for their defense. It drew a lot of attention in the art world, since Mr. Kurtz was a founding member of the Critical Art Ensemble, which uses art to examine the impact of science and technology on consumer culture.

But for Dr. Ferrell the time following the indictment was brutal. He had three strokes and two recurrences of cancer.

According to Mr. Grail, by October, he couldn't fight anymore.

"I recommended the best course of action that was available at that moment," the attorney said.

His client pleaded guilty, but that was before Judge Richard J. Arcara heard oral argument on Mr. Kurtz's motion to dismiss.

"It certainly seems unfair," said Susan Low Bloch, a Georgetown law professor. "It feels wrong."

Dr. Ferrell could seek to reopen his case for extraordinary reasons, she said, but she was unsure if he would succeed.

"You might get the judge to overturn his own verdict," said Ms. Bloch.

What cannot happen, though, is for Judge Arcara to take the matter up on his own.

Former U.S. District Judge Robert J. Cindrich said he would not be authorized to consider the issue without Dr. Ferrell first requesting it.

"It doesn't seem right, does it?" Mr. Cindrich asked.

He criticized the government for pushing the charges.

"The guy was sick, and the case should have never been brought in the first place," Mr. Cindrich said.

But, because Dr. Ferrell was so ill, Mr. Grail had no choice but to let him plead.

"The real practical side is you're standing next to a client who might die if you push him through a trial," Mr. Cindrich said.