A three-judge bench headed by Chief Justice Iftikhar Chaudhry disqualified Gilani in response to several petitions that had challenged the National Assembly Speaker's decision not to disqualify the premier following his conviction of contempt.
The bench ruled that the post of premier had been vacant since April 26, when another seven-judge bench had convicted Gilani of contempt for refusing to reopen graft cases in Switzerland against Zardari.
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