At a press conference earlier this month, the Citizens Whistle Blowers Forum had levelled several allegations against the company. The PwC, however, had denied all the charges.
The letter to Jaitley, shared by senior lawyer Prashant Bhushan who is one of its members, lists the charges against the audit major, including that of alleged "forgery".
"In these cases, it appears, prima-facie, that the authorities have either avoided taking action or action taken by them is grossly inadequate," the letter says.
The PwC had issued a statement, rejecting the allegations. "We deny the allegations made. PwC has always complied and will continue to comply with applicable laws and regulations and any suggestion to the contrary is merely speculative."
Apart from Shah, RTI pioneer Aruna Roy, former finance secretary EAS Sharma, Jagdeep Chhokar of the Association for Democratic Reforms, former navy chief Admiral Ramdas and former Chief Information Commissioner Wajahat Habibullah are the members of the forum.