The crisis within Liberal Democrat ranks over allegations of sexual harassment against Lord Rennard will deepen today as the peer plans to return to the party's ranks in the Upper House.
Party leader Nick Clegg has made clear that the former Lib Dem chief executive should apologise to the female activists who made the claims before the whip is reinstated.
But Lord Rennard strenuously denies the allegations and refuses to apologise, setting up a showdown which will test Mr Clegg's authority.
Lib Dem Lord Carlile, who has been providing legal advice to Lord Rennard, raised the prospect of a court battle with the party leadership if the whip was withheld.
The allegations were investigated by senior barrister Alistair Webster QC who concluded that they could not be proved beyond reasonable doubt, which ended disciplinary proceedings against Lord Rennard.
But he recommended that the peer should apologise to the women involved as a matter of "common manners".
Chief whip Lord Newby and the party's leader in the House Lord Wallace can decide to withhold the whip from Lord Rennard.
If they do then he would almost certainly appeal, triggering a vote of the party's peers whether to readmit him to the Lib Dem group in the Lords.
But a number of Lib Dem members have suggested that his refusal to apologise brings the party into disrepute, which could trigger a new disciplinary process resulting in the whip being suspended.
The Regional Parties Committee will meet to consider the possibility of fresh disciplinary action in response to the complaints.
But Lord Rennard won the backing of Lib Dem Euro MP Chris Davies, who played down the allegations against the peer and attacked Mr Clegg's handling of the row.
He told BBC Radio 4's Westminster Hour: "This isn't Jimmy Savile, it is touching someone's leg six years ago, at a meeting, through clothing.
"This is the equivalent of a few years ago, an Italian man pinching a woman's bottom. How much more must this man be made to suffer through the media condemnation that comes out day after day fed by the party leadership?"
Mr Davies added: "The whole thing has become like the Salem witch trials ... A good man has been publicly destroyed through the media with the apparent support of Nick Clegg. It is completely out of proportion, nonsense and outrageous."
Lord Carlile warned the row could escalate during an interview on the Sky News Murnaghan programme.
He said: "Here, we have a situation in which there has been found to be no case against Lord Rennard but he is being lined up against the wall by people who are trying to force him to apologise in a way no lawyer would advise and in which he should not apologise for all kinds of reasons."
If the whip was removed then "the matter could unfortunately end up in the public law courts", he warned, adding "nobody wants that to happen and I don't begin to understand why Nick Clegg has intervened after a process which has been concluded in Lord Rennard's favour".
Mr Webster said he had not published his report because of clear legal advice regarding data protection laws and redacting the details would "deprive it of any sensible context".
And he added: "The suggestion that Lord Rennard might wish to apologise was not one I envisaged as being contentious.
"I viewed Lord Rennard, from the weight of the evidence submitted, as being someone who would wish to apologise to those whom he had made to feel uncomfortable, even if he had done so inadvertently. I would consider it to be common manners."
Mr Webster said evidence from an independent statement had helped him to a conclusion that "there was credible evidence that events had occurred which had caused distress".
Lib Dem Cabinet minister Danny Alexander backed Mr Clegg's stance on an apology.
He said Lord Rennard "can't have it both ways" by claiming that the Webster review cleared him while refusing to comply with its recommendation to apologise.
"He should apologise because he wants to continue to be a member of the Liberal Democrats and this is the recommendation that's been made by the internal disciplinary process, it's as simple as that," Mr Alexander said.
He told BBC1's Sunday Politics the the party's peers would have to "take a view for themselves" as they had the power to decide who had the whip.
Former leader Lord Ashdown signalled the irritation felt within the party at Lord Carlile's role.
"I fear he is advising Chris Rennard as a lawyer, but not as a friend," he wrote on Twitter.