By Syed Shoaib Hasan
BBC News, Karachi
A Pakistani court has resumed hearing the appeals of four men convicted in the Daniel Pearl murder case.
Daniel Pearl was kidnapped and beheaded in 2002
The main accused, Ahmed Omar Sheikh, was awarded death for masterminding the murder. Others got life imprisonment.
But President Musharraf in his memoirs indicated the murder of the American journalist may have been planned by al-Qaeda leader Khalid Sheikh Mohammad.
Defence lawyers say this information may be useful in proving Omar Shaikh's innocence in the case.
Ahmed Omar, also known as Sheikh Omar, is Pakistan's most famous Muslim militant.
He and his co-defendants are said to be members of the outlawed radical Muslim organization, Jaish-e-Mohammad.
Daniel Pearl was kidnapped in Karachi on 23 January, 2002, while investigating a story on radical Muslim groups for the Wall Street Journal .
On 21 February, a video CD was delivered to the US authorities showing him being murdered.
The four men -Salman Saqib, Fahad Naseem, Sheikh Mohamamad Adil and Ahmed Omar - were arrested and charged with the murder over the next few weeks.
On 15 July, 2002, an anti-terrorism court passed its verdict in the case.
However, doubts have remained over how many people were involved and who actually carried out the killing.
The hearing of appeals by the high court in Pakistan's southern port city of Karachi started after a break of four years and numerous delays.