New York ? A veteran civil rights lawyer was convicted Thursday of crossing the line by smuggling messages of violence from one of her jailed clients — a radical Egyptian sheik — to his terrorist disciples on the outside.

The jury deliberated 13 days over the past month before convicting Lynne Stewart, 65, a firebrand, left-wing advocate known for representing radicals and revolutionaries in her 30 years on the New York legal scene.

Stewart slumped in her chair as the verdict was read, shaking her head and later wiping tears from her eyes. Her supporters gasped upon hearing the conviction, and about two dozen of them followed her out of court, chanting, “Hands off Lynne Stewart!”

She vowed to appeal and blamed the conviction on evidence that included videotape of Osama bin Laden urging support for her client. The defense protested the bin Laden evidence, and the judge warned jurors that the case did not involve the events of Sept. 11, 2001.

“When you put Osama bin Laden in a courtroom and ask the jury to ignore it, you’re asking a lot,” she said. “I know I committed no crime. I know what I did was right.”

Lawyers have said Stewart most likely would face a sentence of about 20 years on charges that include conspiracy, providing material support to terrorists, defrauding the government and making false statements. She will remain free on bail but must stay in New York until her July 15 sentencing.

The trial, which began in June, focused on the line between zealous advocacy and criminal behavior by a lawyer. Some defense lawyers saw the case as a government warning to attorneys to tread carefully in terrorism cases.

Stewart was the lawyer for Omar Abdel-Rahman, a blind sheik sentenced to life in prison in 1996 for conspiring to assassinate Egyptian President Hosni Mubarak and destroy several New York landmarks, including the U.N. building and the Lincoln and Holland tunnels.