Lawyers for the group say the lecture was just an academic political debate The Zimbabwe authorities have detained 46 people for attending a lecture on the unrest in North Africa and the Middle East.
The group has been charged with treason for allegedly seeking to emulate the protests which toppled the leaders of Egypt and Tunisia.
They were arrested on Saturday and their lawyers said they would appear in court for a bail hearing on Thursday.
If found guilty of treason they could face a death sentence.
The activists, trade unionists and students were attending a meeting in Harare entitled “Revolt in Egypt and Tunisia: What lessons can be learnt by Zimbabwe and Africa?” when it was raided by police.
The talk was being presented by Munyaradzi Gwisai, a former lawmaker in the opposition Movement for Democractic Change (MDC) who runs the International Socialist Organisation pressure group and was among those detained.
Media reports said a video projector, laptop and two DVDs were seized.
Zimbabwean media said police had information that the group were attempting to organise illegal street protests against the government.
Defence lawyers say the lecture was an academic debate, but the group have been charged with attempting to overthrow President Robert Mugabe, who has been in power since 1980.
“They appeared in court this afternoon and they are facing charges of treason or alternatively subverting a constitutionally-elected government,” lawyer Alec Muchadehama told the AFP news agency.
He said the case would continue on Thursday, where would also raise complaints that his clients were beaten by the police.
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