Gilani, who is accused of failing to reopen corruption cases against President Asif Ali Zardari, pleaded not guilty.
Helicopters buzzed over the capital and roads were blocked to traffic ahead of the hearing in Islamabad.
Gilani has said the charges were politically motivated and that the president had immunity as head of state.
Both Gilani and Zadari are leaders of the ruling Pakistan Peoples Party.
Gilani could face a prison term and lose his post if found guilty.
Analysts say the case is unlikely to lead to the fall of the government, but will continue to paralyze the country and further boost the power of the country’s military.
The accusations against Zadari stem from Swiss cases dating back to the 1990s when his wife, Benazir Bhutto, was prime minister.
He was convicted in absentia in 2003, but the charges were dismissed during the appeals process at the request of the Pakistani government following a controversial 2007 amnesty law adopted under former President Pervez Musharraf.
compiled from agency reports
Source Article from http://www.rferl.org/content/pakistan_gilani_corruption_/24481887.html
