Why the gay sex issue isn't going to go away for Tim Farron €“ and what he should say next time he's asked

It's a question Tim Farron must lie awake at night dreading.

Channel 4's Cathy Newman once again pinned the Liberal Democrat leader on his personal views on gay sex.

'Metropolitan remainers might like what they hear from you on Brexit,' she began.

'But what about social issues. Take for example, a while back I asked you whether it was true you believed homosexuality was a sin and you struggled to answer. Now you have had a while to consider that question, what is the answer?'

He replied: 'I don't think I struggled to answer it at all, Cathy. I think I'm not in the position to make theological announcements over the next six weeks. I'm not going to spend my time talking theology or making pronouncements.' He went on to stress his political support for gay rights: 'As a Liberal, I'm passionate about equality, about equal marriage and about equal rights for LGBT people, for fighting for not just for LGBT rights in this country but overseas. 'Just because I'm Christian, it would be a bit boring for everybody to spend the next weeks asking me to make theological announcements that I'm not going to make.' In a campaign where Farron will look to pitch his party as the only credible option Remain option, it is a stumbling block he doesn't need. As a quick Google search will show, the issue is one that could well dominate public views of him. 

The reaction on social media was predictable. Until moments before hailed as a hero of the 48 per cent, Farron was immediately derided as an 'absolute disgrace'.

There are layers upon layers of questions behind this issue. Is it right for Cathy Newman to repeatedly ask about this when it doesn't have any relevance to Farron's policy positions? Is it now impossible for a British Prime Minister to be anything other than a social liberal? Are conservative Christians barred from positions of high office in UK politics?

But the most pressing seems to whether a politician's personal views matter if it doesn't effect his policies.

When Tony Blair was asked if he prayed the concern was whether it would affect his judgment about going into Iraq. 

But no such concern can be applied to the Lib Dem leader. Farron has gone to great lengths to stress his pro-LGBT rights credentials.

He voted for the gay marriage legislation in 2012 and insists his abstentions later in the bill's process were over concerns about transgender people's protections. Out of the major party leaders he has been the most outspoken on gay rights – certainly more so than the daugher of a vicar Prime Minister. 

As an evangelical Christian, Farron clearly believes in private that gay sex is sinful. As a liberal he won't enforce that on anyone and wants maximum freedoms for LGBT people to marry alongside heterosexual people. But that is a difficult and uncomfortable nuance to communicate to a hostile and religiously illiterate press pack. 

The reaction to Farron's latest interview has shown that personal views, no matter how inconsquential, do matter. However firmly he boasts of his support for equal marriage and transgender rights, his refusal to deny gay sex is sinful will dog him. 

Private views matter, however clearly they are separated from public policies. So here's what Tim Farron needs to say next time Cathy Newman asks him about gay sex.

'I'm a traditional Christian, and that goes with certain views about sex and sexuality. It also means, for instance, that I think the right place for sexual activity for heterosexual people is within marriage, but I notice you don't press me on that.

'However, I'm perfectly capable choosing to live in a particular way myself without feeling I need to inflict that on the rest of the country. And as a Liberal Democrat I stand for freedom of choice, justice and equality for everyone, including gay, lesbian and transgender people. I don't judge anyone and I don't condemn anyone. I need to have the freedom to exercise my conscience and they need to have the freedom to exercise theirs, and my record shows that I have fought and will fight for that as hard as ever I can. 

'As a Liberal Democrat, I categorically reject the idea that everyone has to be forced into an ideological straitjacket before they can contribute to the political life of this country. I hope we can move on from this obsession with sex and sexuality and talk about the things that really matter about this election.'

Will it silence his critics? Possibly not – but what comes across as the non-answers he's given so far haven't done so, either.