Everything you need to know about the Lib Dem sexual harassment scandal in five minutes

What's going on?

Allegations of sexual harassment by Lord Rennard have come to light and there are concerns they were brushed under the carpet by the Liberal Democrat leadership. Nick Clegg is front and centre of the row after he released a confusing statement about what he knew and when.

Who is Lord Rennard?

He's not exactly a household name, but inside the Westminster bubble Chris Rennard is celebrated as the backroom strategist responsible for the success of many of the Lib Dems' local campaigns. He enjoyed extraordinary respect and influence in the party's Cowley Street headquarters as the mastermind behind campaigns which entrenched the party in local areas.

He was director of campaigns and elections between 1989 and 2002 and then chief executive from 2003 to 2009, when he stepped down – ostensibly for health reasons. At the start of his employment the party were a half-remembered appendix to UK politics. By the time he left, they were a professional operation poised to enter government in coalition.

What are the allegations against him?

At least ten women have complained about sexual harassment, including inappropriate touching and propositions, from the peer. Former party activist Alison Smith is reported to have spoken to chief whip Paul Burstow and Jo Swinson, current women's minister, about the behaviour in 2007. Bridget Harris, former special adviser to Clegg, is reported to have complained to her line manager as far back as 2003. Smith told Channel 4 that Rennard's decision to step down had nothing to do with health reasons but came after party figures told him to leave the stage due to the allegations.

Liberal Democrat sources say rumours around Rennard have been circulating for years although there has been little specific information. Journalists from several newspapers have been sniffing around the issue for some time.

Rennard strenuously denies all the allegations. In a statement he said: "I absolutely deny any suggestion of improper touching, nor did I invite a woman to join me in my room. I note that these alleged instances supposedly took place in public bars with other people present. I am disappointed and angry that anonymous accusations from several years ago are once again being made public in this manner in a clear attempt to damage my reputation. Let me reiterate that in 27 years working for the Liberal Democrat party, not a single personal complaint was ever made against me to my knowledge."

What did Clegg know?

Clegg's Sunday night statement said he "did not know about these allegations until Channel 4 informed the party of them shortly before they were broadcast". But he later adds:

"I am angry and outraged at the suggestion that I would not have acted if these allegations had been put to me. Indeed, when indirect and non-specific concerns about Chris Rennard’s conduct reached my office in 2008, we acted to deal with them."

This comment was significantly different to that made by Vince Cable on Sunday morning news programmes. Asked if he was aware of complaints, he said: "Absolutely not." He added: "Nick Clegg has also said he was not aware of these allegations until they appeared on TV last week."

Clegg said his then-chief of staff Danny Alexander had a word with Rennard. The chief executive categorically denied the reports. In what could become the most important section of the Clegg statement, the deputy prime minister then said: "As my office only received concerns indirectly and anonymously, as those involved understandably wanted to maintain their privacy, there was a limit to how we could take this matter forward following Chris Rennard's resignation."

Several facts in this sentence are disputed by Channel 4. Smith and Harris are not thought to have complained anonymously. Smith told journalists she was lost in a "Kafkaesque" nightmare in which the party refused to act on her complaints because no-one had made a complaint. And then there is the suggestion Rennard was essentially forced out due to the rumours, rather than because of his publicly-stated health reasons.

Clegg then said: "It is incorrect to state that there was any other separate inquiry by my office or anybody in it." Channel 4 says several women told them Jo Swinson had been carrying out investigations.

What happens next?

There are two investigations. One will look into the procedures the Lib Dems have in place for complaints of this sort and whether they need to be improved. After three days of pressure, Clegg accepted that this needs to be independently chaired. A second disciplinary investigation will be conducted into the specific allegations against Rennard. There may also be a criminal one. Labour MP John Mann is writing to Scotland Yard to urge police to open a formal investigation.

How will this affect the Eastleigh by-election?

A massive scandal blowing up days before a pivotal by-election sounds like a disaster for Clegg, especially given recent polls suggest a surprising Tory resurgence in the seat. But as one activist told the Times: "If Chris Huhne lying doesn't derail us, neither will Rennard".  There is a certain irony to the truth of that statement. It was Rennard who helped the Lib Dems become fierce local campaigners, and that quality has put the party in a good position in Eastleigh. Despite plunging national poll ratings and a by-election triggered by a criminal conviction against one of their first Cabinet secretaries, the party has used its local strength to put in a solid performance in the Hampshire seat. If Eastleigh voters keep seeing the poll as a test of local performance, the party might be able to shield itself from damage.

Should the Lib Dems keep the seat, it will raise difficult questions for David Cameron. Before the Rennard scandal, he could pin the blame for a loss on Maria Hutchings, his wildly off-message Tory candidate. After the scandal, it will be difficult for him to explain how he could not take a seat off a deeply unpopular political party in the middle of a major scandal.