New Delhi, March 21 : Amid the Opposition demand for a Joint Parliamentary Committee to probe the Hindenburg report on the Adani group, there have been several instances when a JPC has been constituted to probe a certain matter. The JPC is constituted with members of both the Houses. The Lok Sabha members are double the Rajya Sabha members in strength, the ruling party will have a majority in the JPC. It has the power to summon a government or non-government individual or a group to give oral evidence. The JPC can obtain evidence from experts, public bodies, associations, individuals suo motu or on a request made by others. If anyone called for witness fails to appear before the JPC in response to a summons, the conduct constitutes contempt of the House. It can take oral and written evidence and call for documents in connection with the matter under its consideration. The proceedings of parliamentary committees are confidential and Ministers are not generally called by the committees to give evidence. However, with the permission of the speaker it may call them. The government may decline to produce a document if it is considered prejudicial to the safety and the the interest of the State. Congress General Secretary Jairam Ramesh said that the demand for a JPC is genuine and it can't be linked to Rahul Gandhi. "How can the Opposition demand for a JPC on the PM-linked Adani scam be linked to the BJP's demand for an apology from Rahul Gandhi on totally baseless accusations. The JPC is on a real, documented scam. The apology demand is a hoax being raised to divert attention from the Adani scam." While the treasury benches are demanding an apology and the chairman in the Upper House and speaker in the Lower House tried to resolve the issue but there was no forward movement. Piyush Goyal accused the Opposition of boycotting the meeting. The constitution of the JPC dates back to the Bofors scandal in 1987 and then in the Harshad Mehta, Ketan Parekh case, Land Acquisition Bill, 2G spectrum allotment, Data Protection Bill. The Bofors JPC was chaired by Congress politician B. Shankaranand. The Harshad Mehta Stock market scam 1992 -- the second JPC was formed in August 1992. It was headed by former Union minister Ram Niwas Mirdha. The third JPC was formed in April 2001. It was assigned to probe the Ketan Parekh share market scam. Senior BJP member Lt Gen Prakash Mani Tripathi (retd) was named the chairman. Soft drink pesticide issue -- The fourth JPC was set up in August 2003 to look into pesticide residues in soft drinks, fruit juice and other beverages and other essential things and was headed by Nationalist Congress Party chief Sharad Pawar. The 2G spectrum case -- The fifth JPC constituted in February 2011 to probe the 2G case and headed by P.C. Chacko. The VVIP chopper scam - on February 27, 2013, which was adopted by voice vote-for formation of a JPC "to inquire into the allegations of payment of bribes in the acquisition of VVIP helicopters by the Ministry of Defence from M/s Agusta Westland and the role of alleged middlemen in the transaction. /IANS