Liberal Democrat president Tim Farron has promised a thorough investigation into strongly-denied allegations that the party's former chief executive behaved inappropriately with women.
Mr Farron insisted internal investigations had been launched "swiftly" when the claims about Lord Rennard were aired by Channel 4 News this week.
And he insisted he was "sure" that Deputy Prime Minister Nick Clegg had not previously known about the accusations - which are said to range across the past decade.
Lord Rennard - a key party strategist and adviser to a succession of Lib Dem leaders before standing down due to ill health in 2009 - has said he is "deeply shocked" by the allegations, which he "strongly disputes" and regards as a "total distortion" of his character.
In the initial Channel 4 report on Thursday, two women claimed Lord Rennard had touched them inappropriately. One of them, Alison Smith, a Lib Dem activist who is now a lecturer at Oxford University, said she had spoken to both the then Lib Dem chief whip Paul Burstow and the party's spokesperson for women and equality, Jo Swinson, about her claims, but claimed no action was taken.
A fresh report by the programme yesterday said more women had come forward with similar stories.
The Lib Dems have launched an internal investigation into the "specific allegations" against Lord Rennard under the party's disciplinary procedures.
Mr Farron is also conducting a review into the way the party dealt with such allegations.
Asked on Channel 4 News if party leader Mr Clegg had known about the allegations, Mr Farron replied: "I do not know, but I am sure that is not the case."
Pressed on whether he believed the Lib Dem organisation had fallen short of its responsibilities, the MP said: "That's what we're going to find out one way or the other."