In 2014, Channel 4 News investigated sexual harassment in Westminster. An exclusive survey of parliamentary staff uncovered a widespread and deep-rooted problem across all political parties.

A third of respondents said they had personally experienced some kind of sexual harassment. And, in the majority of cases we heard about, the victim was under 25.

In the wake of our investigation, political parties pledged to take action. They promised to set new rules, introduce complaints procedures, and make it easier for victims to come forward.

But now, the scandal has emerged again, with allegations of inappropriate behaviour by dozens of MPs and ministers.

So what has actually changed since 2014? Have political parties stuck to their promises to help tackle the problem?

Conservatives

After the Channel 4 News investigation in 2014, the Conservatives launched a new code of conduct for MPs.

However, they were under no obligation to sign up – it was “on a voluntary basis” only.

The Conservatives also made clear that individual cases were for MPs to handle themselves, rather than the party. In theory, that could mean that staffers have to complain to the very people who are harassing them.

In a letter to MPs, the party’s chief whip said: “I hope you may consider adopting [the code of conduct] your office,” but explained it was “entirely a matter for you to handle”.

Reports say that David Cameron, who was then prime minister, tried to introduce a create a mandatory code of conduct which would have given staffers the right to seek arbitration. But the Evening Standard revealed that this was blocked by the party’s powerful 1922 Committee of backbench MPs.

The committee’s chairman, Graham Brady, told the newspaper: “Our view was that matters of that sort should be for the whole House of Commons, not one side.”

Channel 4 News asked the Conservative Party whether it had made any further changes to its harassment policy since 2014. We were directed to a statement from a Conservative minister made this week, which did not address any internal party procedures and instead focused on what the House of Commons can do as a whole.

On the Conservatives’ website, we could not find any guidance on how to report abuse – although this may be in restricted members-only areas of the site. We are also not aware of any procedures available for protecting victims’ anonymity.

Labour

Under the leadership of Ed Miliband in 2014, the party pledged to introduce an individual complaints process, which it said would be in force after Easter of that year.

Labour confirmed to FactCheck that rules were indeed updated in May 2014 which provided “a procedure for complaints against Labour MPs by MPs’ staff”.

In July this year, the party’s national executive committee developed a procedure to deal specifically with sexual harassment allegations.

Labour says that complaints are initially considered by a sexual harassment panel, with all names kept anonymous. Under the system, victims will “never be required to confront the respondent face to face”.

The party has also set up a dedicated hotline for its members which gives advice on how to make a formal complaints and get support.

Lib Dems

In 2013, the Lib Dems were rocked by allegations of sexual harassment by one of the party’s most senior figures, Lord Rennard, following a separate investigation by Channel 4 News. The peer strongly denied the allegations and a police investigation was dropped due to insufficient evidence.

But a review commissioned by the party criticised the way complaints had been dealt with by officials. It said there was a “reluctance to investigate”, and that “much more could and should have been done”.

The report added: “The addressing of complaints needs to be a higher priority for the party and not just something to be dealt with in a crisis.”

The Lib Dems told us that rules were changed in 2014 to lower the burden of proof needed to disqualify members over harassment allegations. They were changed from criminal standards (to prove allegations “beyond reasonable doubt”) to civil standards (based on “the balance of probabilities”).

The party told us that members are able to make complaints anonymously and that the party tries its best to maintain this anonymity if the victim requests it.

It is not clear how this works in practice. Guidance available on line says complaints should be lodged using an online form which “gives us permission to show [the information] to the person in question”. But there does not appear to be any option for anonymity on the form – although it’s possible that it is done on a more ad hoc basis.

It also appears that the Lib Dems either missed or fluffed a scheduled review of its complaints guide that was due last year.

When FactCheck reviewed the online guidance document on Monday, it was dated 2014 and stated: “This policy will be reviewed every 2 years. Next review date: Feb 2016.”

This suggests that either the review did not take place, or was not published. However, a party spokesperson claimed: “The guidance was reviewed in 2016 and is kept under review. The website is in the process of being updated.”

After FactCheck asked the Lib Dems about this, the document has been edited and is now dated 2016. It says: “This policy is kept under review. This is a living document and changes may be made to it prior to the review date.”

Speaker

The Speaker, John Bercow, is the highest authority in the House of Commons and remains impartial from party politics.

In 2014, he set up a confidential hotline for MPs’ staff, which he said was a “safety net designed to complement existing pastoral care”.

The phone line is open to all parliamentary staff who have been bullied, harassed or abused.

The latest figures show that staff made almost 500 calls over the last two years. On average, that’s roughly one call every other day.

But the service has been criticised because it does not actually take any action against abusers. One union official called it “about as useful as a phone call to your mum”.

She explained: “There is no Human ­Resource department. The helpline can’t help you. It can offer advice but ultimately it will suggest you contact the MP directly.”