Egypt begins a two-day runoff presidential vote Saturday pitting former prime minister Ahmed Shafiq against Muslim Brotherhood candidate Mohamed Morsi.

The balloting comes amid political turmoil, following a Supreme Constitutional Court ruling early in the week overturning a law passed by the Islamist-led parliament that barred senior officials from ousted president Hosni Mubarak’s government – like Shafiq – from holding office. The justices – holdovers from the Mubarak era – also cited legal problems with the last round of parliamentary elections and called for the the Islamist-led parliament to be dissolved.

Some leading Islamists accused the country’s ruling military council of using the court to stage a de facto coup. But the council said the presidential runoff would go ahead as planned.