Drug Scandal

On October 16, 2006, Shoaib was suspended by the PCB, along with Mohammed Asif after the pair were tested positive for a performance-enhancing substance nandrolone. They were consequently pulled from the ICC Champions Trophy 2006. Former PCB chairman later stated that he had always suspected Shoaib of substance abuse due to his consistent "reservations" to drug tests. Pakistan captain Inzamam ul Haq had also previously complained about Shoaib's drug abuse but was not acted upon by the PCB. Pakistan news reports state that federal capital police had arrested Shoaib along with drugs some three years ago.

Shoaib was then reportedly seen participating in the smoking of marijuana at a night club, violating the curfew for the team in their test series against England.
Shoaib immediately declared his innocence and he declined knowingly taking any performance enhancing drugs. In a statement issued to the press, he claimed that he could never cheat team-mates or opponents. During a hearing with the PCB Anti-Doping Committee (ADC), he along with Asif maintained taking non-steroidal dietary supplements. He, however, failed to convince the committee of his innocence. In its report submitted to PCB, ADC recommended a two year ban.
On November 1, 2006, PCB handed down a two-year suspension to Shoaib and a one-year suspension to Mohammad Asif, banning them from professional cricket during the period. Shoaib had subsequently been added to Pakistan Olympic Association list of doping offenders. However, on December 5, 2006, he was cleared on appeal.

Acquittal

On December 5, 2006 Shoaib and Mohammad Asif were acquitted by the tribunal appointed to review their appeals against the drugs ban imposed on them by an earlier committee. The three-man committee, headed by Justice Fakhruddin Ebrahim, voted two to one in favour of the acquittal. Haseeb Ahsan, former Test cricketer, and Ebrahim were in favour of the acquittal while the third member, Danish Zaheer, dissented. “Exceptional circumstances” were cited including discrepancies between the instantaneous offence charges of doping that were laid and the quick delivery of a very harsh verdict. The complete drug testing procedure was concluded to have been technically flawed as it did not follow standard procedures. Other established facts by the committee included that the duo were not aware of the banned drug to be present in their supplements because PCB itself had not informed them of the dangers of contaminated supplements.

Both Shoaib and Mohammed Asif were thankful to the PCB chairman Nasim Ashraf for giving them a fair trial and their team mates, captain, and coach for the moral support. They did not however play in the 2006 Nov-Dec West Indies vs. Pakistan series held in Pakistan because the PCB has recommended that they play domestic games first to recover form and fitness.
However, WADA, the World Anti-Doping Agency was to challenge Pakistan's decision to lift bans on fast bowlers Shoaib and Mohammad Asif by taking the case to the Court of Arbitration for Sport in Lausanne, Switzerland. The ICC, cricket's world governing body, has supported the WADA appeal adding that it was committed to a dope free game.

On March 1, 2007, Shoaib and Asif were ruled out of the Pakistani squad for the 2007 Cricket World Cup by team officials, minutes before the squad was to depart for the West Indies. The team management along with the PCB said their injuries were too severe to risk taking them to the Caribbean. Since neither of the two had been declared fit they had not undergone official doping tests.
However, on July 2, 2007, the Court of Arbitration for Sport later dropped the case, ruling it had no jurisdiction to challenge the decision made by PCB.