Supporters of a Conservative MP found to have committed an “egregious” breach of lobbying rules are pushing for a free vote to help him avoid suspension from the Commons and want to scrap the watchdog that handed down the punishment, describing it as a “kangaroo court”. They told the Guardian a “rearguard action” was mounting to help Owen Paterson avoid the 30-day suspension and subsequent possible byelection if 10% of constituents in his North Shropshire seat signed a recall petition. Although the former cabinet minister was found by parliament’s standards commissioner and standards committee to have broken lobbying rules while working as a paid adviser to two companies, a group of backbenchers and some ministers have said it is wrong he has no route to appeal against the finding handed down on Tuesday. They also believe he has already been punished enough given the investigation has gone on for two years, and Paterson claimed it played a “major role” in driving his wife, Rose, to kill herself last summer. A vote is likely to be called in the middle of next week to approve the standards committee’s recommendations. However, while these votes are usually a formality and pass without dissent, the fact Paterson has protested his innocence is likely to force a division, backed by other Tory MPs. They would only be able to win with the government’s support, so are hoping that a free vote will be called that will allow MPs on the payroll to vote as they choose. But a Tory insider guessed it may be made clear how their side should vote by being told which lobby the chief whip would be going through. There have only been two proper votes on a standards report’s suspension recommendation – in 1947 and in 1990 – that both failed. A minister called bodies that ruled against Paterson a “kangaroo court” and said they would probably abstain. “Either we vote to exonerate him and then it’s ‘bastard Tories as usual’, or we vote to convict him and then there’s loads of bad blood,” they said. Iain Duncan Smith said the investigators’ report “shows this system is completely broken and has been for some time”. The former Conservative party leader told the Guardian: “The more I read the report, the more I became concerned and it backed up my view that we should abandon this process and go for a quasi-judicial one with QCs and judges. “It’s currently a very bad process that doesn’t know if it’s a prosecutor or just an investigator and it gives MPs no chance of appeal. It is deeply unfair; it’s time that we reset this and brought it to a quasi-judicial process.” However, a considerable number of Conservatives believe the finding against Paterson was fair and that it would be a “terrible look” to overrule the independent body meant to adjudicate on MPs’ alleged wrongdoings and prevent politicians from in effect marking their own homework. A former Tory cabinet minister said Paterson was “bang to rights” and that even if the sleaze watchdog system did need reform, this was not the moment for it. Downing Street has still offered no direct criticism of Paterson, with Boris Johnson’s spokesperson saying this week that “the standards regime is a matter for the House of Commons” and that the prime minister was “mindful of the pain faced by the Paterson family”. Chris Bryant, chair of the Committee on Standards said: “I would urge everybody to read the report in full with a fair and open mind. The committee considered Paterson’s complaints about the process and rebutted each of his points in the report. In the end the facts speak for themselves.”