Iran's conservative judiciary also sentenced a member of an Islamic vigilante group to two years in jail in the case.
The lawyers were charged with slandering senior government officials in the videotape, which they allegedly helped make. They have denied making the tape. The case was the latest round in a battle between hard-liners and reformists in Iran.
Shirin Ebadi, a liberal women's rights activist, said she and fellow lawyer Mohsen Rahami, a university professor and cleric, were sentenced Wednesday to a five-year vocational ban in addition to a 15-month suspended prison term by a Tehran court following a closed-door trial.
"I'm innocent. What I did was part of my legal responsibilities as a lawyer to provide evidence in a court case to the responsible authorities. I would have committed a crime if I had done otherwise," Ebadi said Thursday. In the videotape, widely circulated in Tehran, Amir Farshad Ebrahimi, a member of a violent Islamic vigilante group, names several senior members of the government and alleges they used his group to attack their reformist opponents.
Iranian state radio in July reported that Ebrahimi had denied his statements in the videotape, saying that the two lawyers had pushed him to make them.
Ebrahimi has been sentenced to two years in jail, the government daily Iran reported Thursday.
Ebadi and Rahami were arrested in July, for what authorities described as "allegations against some officials" made in the videotape, but were released on bail after spending about three weeks in jail. They were later tried behind closed doors due to "national security." Details of the trial are sketchy.
The controversy over the videotape is considered to be part of a power struggle between reformists, led by President Mohammad Khatami, and hard-liners, who dominate many parts of the establishment and look for support from Iran's supreme leader, Ayatollah Ali Khamenei.
The judiciary has become the hard-liners' most powerful tool. In the past six months, it has closed many reformist newspapers and ordered the detention of several pro-reform journalists and activists.
The vigilantes are controlled by hard-liners in the Iranian establishment. Attacks by club-wielding vigilantes in late August on a conference of reformist students left about 100 participants injured, 40 seriously, conference organizers said.