Angela Rayner today said Labour would introduce a new independent standards watchdog to probe allegations of wrongdoing by ministers as she claimed corruption is 'rife right through this Conservative government'.
The watchdog would have the power to launch investigations and demand the sacking of ministers.
Ms Rayner said the existing standards system is 'broken' because Boris Johnson can reject findings that Cabinet members have breached the ministerial code, as he did with Home Secretary Priti Patel.
To replace the current 'alphabet soup of different committees and advisers', Labour's proposed watchdog would replace the 'toothless' Advisory Committee on Business Appointments (Acoba) that advises ministers on post-Government jobs.
Former ministers would be banned from lobbying, consultancy or any paid work relating to their old roles for at least five years under the plans which Labour would roll out if it wins the next general election.
The watchdog would also have powers to impose financial sanctions on former ministers who break the rules to close the 'revolving door' between public office and lucrative roles for firms they used to regulate.
Angela Rayner today said Labour would introduce a new independent standards watchdog to probe allegations of wrongdoing by ministers as she claimed corruption is 'rife right through this Conservative government'
Ms Rayner will set out the party's plans to tackle sleaze in Westminster during a speech today as the Conservatives continue to be battered by a standards row.
'The current regime is no longer working precisely because we have a Prime Minister who is shameless in breaking the rules and won't enforce consequences on others who break them,' she is set to tell an Institute for Government event.
'Corruption – that is the word – is happening in plain sight and it is rife right through this Conservative government.
'Why do the rules and standards matter? Because the people who are picking up the bill for this corrupt government are the taxpayers whose money ministers are wasting and abusing.
'Our democracy cannot hinge on gentleman's agreements – it needs independent and robust protection from Conservative corruption.'
Ms Rayner is expected to say that any current ruling by the adviser on ministers' interests is 'not worth the paper it's written on' because the Prime Minister can simply reject it.
To illustrate this, she will use the example of Sir Alex Allan finding Ms Patel had broken the ministerial code with behaviour that amounted to bullying her staff.
Mr Johnson overruled the finding and stood by Ms Patel rather than forcing her to stand down. Sir Alex resigned as the adviser on ministers' interests instead.
'The commission will have the power to access any evidence they need and there will be clear sanctions for breaches of the code so the Prime Minister is no longer judge and jury when it comes to the conduct of ministers,' Ms Rayner is expected to say.
Former ministers would be banned from lobbying, consultancy or any paid work relating to their old roles for at least five years under the plans which Labour would roll out if it wins the next general election
Legal advice is understood to have suggested the watchdog could not be handed the power to sanction ministers against the leader's will but Labour said it would accept any decisions as 'binding'.
A Cabinet Office spokesman said: 'The Government has committed to continually reinforcing high standards of conduct in public life so the public can have trust and confidence in the operation of government at all levels.
'As we have said previously, we will carefully consider the reports by the Committee on Standards in Public Life, Nigel Boardman and others, before setting out a full update to Parliament in due course.
'It's absolutely right that we fully take account of all of the evidence and work up the best solutions before responding.'