More than one intelligence team and agency has investigated the assassination in detail but not a single report or book has uncovered any substantial evidence about the perpetrators

Preliminary Investigation Report by JIT: The report of the first JIT set up by the then Musharraf-led caretaker set-up was revealed by the then spokesman for the interior minister Brig (retd) Javed Iqbal Cheema.

According to him, Benazir Bhutto died from a skull fracture caused by the impact with the lever of the sunroof of the car she was in. The pressure with which she hit the lever was caused by the bomb explosion that had taken place.

Brig Cheema also mentioned a medical report prepared by Principal of Rawalpindi Medical College (RMC) Dr Musaddaq Khan which too referred to the injury caused by the sunroof of the jeep. Earlier the doctor had claimed that Ms Bhutto died of a bullet injury.

The second major revelation by the brigadier was the audio recording of the intercepted telephone call by Tehrik-i-Taliban Pakistan (TTP) chief Baitullah Mehsud in which he ostensibly discussed the assassination of Ms Bhutto.

Scotland Yard Report: The Scotland Yard’s report into the assassination of Ms Bhutto was released on Feb 8, 2008.

The four-page investigation report said Ms Bhutto died of a severe head injury sustained from the effect of the bomb blast.

However, in the same report, a UK Home Office Pathologist, Dr Nathaniel Cary, said that he was “unable categorically to exclude the possibility of there being a gunshot wound to the upper trunk or neck” of Ms Bhutto.

Significantly, the team from Britain’s investigation agency was only asked to determine the cause of death by the then government.

However, its conclusions were inconclusive in the absence of an autopsy report and the lack of forensic evidence from the site of the incident – the site was washed by powerful hoses within hours of the incident.

UN Commission Report: Issued on April 15, 2010, the UN Commission’s report did not reveal any explosive truths but it was a damning indictment of the then government, the Rawalpindi police and intelligence agencies.

It said that despite being aware of the threats to her life, the federal government under General Musharraf did little more than pass on information of the threats to Ms Bhutto and to provincial authorities.

It criticised the Rawalpindi district police’s actions and omissions such as its decision to hose down the crime scene and its failure to collect and preserve evidence.

The report added that the intelligence agencies and other government officials hampered investigations, pointing out that police officials, fearing intelligence agencies’ involvement, were unsure of how vigorously to pursue the investigations.The report said Ms Bhutto faced threats from a number of sources; including elements in the Pakistani establishment.

The commission also found PPP’s security arrangements inadequate.

Punjab Police Report provided to the UN Commission: This report said that 12 militants reached Rawalpindi a day before the assassination.

Four of the militants tasked to kill Ms Bhutto belonged to Darul Uloom Haqqania in Akora Khattak near Peshawar, which is run by Maulana Samiul Haq, the pro-Taliban Amir of one faction of JUI. Three of the 12 militants were killed; of the remaining nine, five were arrested by police.

This report considered the TTP the main culprit.

The article and book on the assassination: Owen Bennett-Jones, a journalist, has written an article titled Questions Concerning the Murder of Benazir Bhutto.

He has highlighted the links of the Pakistani security establishment to the militants in the tribal areas and discussed well-known militants such as Qari Saifullah Akhtar. The latter is accused of having attempted to overthrow the second government of Ms Bhutto and of carrying out the October 2007 bombing.

Jones has quoted PPP followers who allege that the assassination was a well-thought-out plan that involved state officials such as General Musharraf. He has also discussed conspiracy theories revolving around President Asif Zardari.

However, the evidence he cites is circumstantial at best.

Amir Mir, a Pakistan journalist, in his book “Bhutto Murder Trail: From Waziristan to GHQ” has also tried to explain the “symbiotic” relationship between the military establishment and the militants.

Whether or not General Musharraf had personally ordered the killing of the PPP leader, argues Mir, he knew that serious plans were afoot to kill her and he didn’t provide adequate security.

He absolves the present PPP leadership and says that President Zardari failed to make any headway in investigations into his wife’s killing because of the resistance of the military establishment.