Peers who commit serious misdemeanours should be kicked out of Parliament, Liberal Democrat leader Nick Clegg has declared.
He made the call as pressure grew for tougher sleaze rules in the Upper House following the wake of cash-for-influence row.
Leader of the Lords, Baroness Royall, has launched two inquiries into claims Labour members were ready to change legislation in return for money.
Lord Truscott, Lord Moonie, Lord Taylor of Blackburn and Lord Snape are accused of entering into negotiations, involving fees of up to £120,000, with Sunday Times reporters posing as lobbyists for a foreign firm. All four strenuously deny any wrongdoing but they could also be subject to a police probe after complaints were filed with Scotland Yard.
Lord Moonie, a former defence minister, also faces separate questions over his decision to give a Parliamentary pass to someone previously stripped of such access because of his arms industry lobbying links.
The four peers will give evidence to the House of Lords interests sub-committee privately this week, and the chairman of the Privileges Committee, Lord Brabazon of Tara, is carrying out a wider review of punishments.
However, it appears unlikely that the peers would be dealt with under new rules if the allegations are proved. That would mean the most serious sanction available was being ordered to apologise to the House.
Mr Clegg said: "It is frankly a scandal that, at the moment, somebody who passes the laws of the land in the House of Lords could actually break the law, maybe in some places very seriously, and not forfeit their place in the House of Lords.
"I am not suggesting for every misdemeanour you should be throwing people out of the House of Lords, but I just think that this whole set of allegations has lifted the lid on an institution which is completely out of step with modern Britain."
