What does the Richmond Park by-election result tell us about Labour, Brexit and next year’s county council elections?

What has happened? Unpredictable 2016 has struck again. The Liberal Democrats managed to overturn former Conservative Zac Goldsmith's 23,000 majority and Sarah Olney won the by-election in Richmond Park.

Why was the by-election called in the first place? Zac Goldsmith - a former Conservative - has been a strong opponent of the expansion of Heathrow Airport. He vowed to resign if the government gave the go-ahead to a third runway. He kept to his word when Theresa May announced that the government was backing the plan at the west London site, and he duly resigned triggering a by-election to stand as an independent.

What was the campaign like? While Zac Goldsmith wanted to make the campaign about the expansion of Heathrow, the Liberal Democrats, who have also opposed extra capacity at the airport, successfully shifted the focus to Brexit and Conservative Theresa May's negotiating strategy.

Zac Goldsmith was a prominent Brexiter in a strongly remain-supporting seat. Liberal Democrat leader Tim Farron has backed the idea of a second referendum in a move which appeared to pay off for the party in Richmond.

What does it mean for Brexit? Very little pragmatically. The new MP for Richmond Park Sarah Olney made the by-election a mandate for her to vote against triggering Article 50. But a single new MP will not stop Article 50 being triggered. She is the representative of one very pro-remain constituency in the country.

Labour MPs, many who have constituencies where a majority voted to leave, cannot be seen to stand in the way of the referendum result, even if they personally backed remain.

But, the result may give the 'soft brexiters' in the government ammunition to push for a less drastic cutting of ties from the European Union.

What does this mean for the Conservatives?

It is certainly a blow. Zac Goldsmith was not their candidate and did not have the party machine behind him, but it erodes Theresa May's wafer thin majority. They have one less MP to rely on to march through the lobbies for them. Zac Goldsmith was likely to back the Conservatives on a variety of issues, even though he would officially have been an independent. The new MP Sarah Olney won't.

And what about Labour? It was a terrible night for Jeremy Corbyn's Labour which received less votes than they have members in the local party. They never expected to win the seat, but to poll quite so badly is already prompting questions about Jeremy Corbyn's appeal and the party's approach to Brexit. One Labour source pointed to the fact that the party's influx of newer members seem to be 'more flexible' and were willing to tactically vote to get rid of Zac Goldsmith. A shift from older generation who were tribally Labour. A worrying development for the party.

And what about the Liberal Democrats?

It is clearly a big boost for the party which has increased its parliamentary representation by 12.5pc and at last has a woman among its MPs. But it still only had nine MPs.

It is an endorsement of Tim Farron's bold strategy to be a vocal opponent of Brexit, and to raise the prospect of giving the country the chance to have second thoughts on leaving the European Union.

But while the strategy plays well in pro-remain Richmond, how it is going down in North Norfolk, which strongly voted to leave the European Union, remains to be seen.

James Wright, the party's prospective parliamentary candidate in Norwich South who has been volunteering in Richmond and helped to get supporters out to the polling station, said he was encouraged by the number of Labour voters switching to vote for the Lib Dems because of their disagreement with their party's position on the EU, but also pro-European lifelong Consevatives voting for the Lib Dems because they felt they had nowhere to go.

But he admits the party is not going to change its fortunes overnight, claiming the bye-election was a building block.

He dismissed suggestions that the party was becoming a one trick pony claiming the NHS had also come up and that would be a big area for them in the run up to future elections.

And what about next year's local elections?

Mr Wright said they had been making big gains for a while in small council elections and by-elections. Membership in Norwich South continues to trickle upwards and pointed to a couple of defections to the party at a local level.

It is not yet clear if county council elections will be a re-run of the European Union referendum, or whether local issues will play more of a role.

Is this sort of tactical voting for a single issue a good thing?

Katie Ghose, chief executive of the Electoral Reform Society, said the by-election had been missing voter choice.

The Green Party, Conservative Party and the UK Independence Party all decided not to stand candidates. She said: 'Many felt forced to vote for candidates who were not their first choice, understandably putting tactics above the expression of their democratic will. It should be obvious that in the 21st century, no one should feel forced to choose between head and heart.'

'Tactical voting is a scourge on our democracy. This is what happens when a two-party voting system collides with the reality of modern politics. It leaves both voters and parties worse off.'

And what about Zac Goldsmith?

He has had a terrible year. He lost to Sadiq Khan in the London mayoral race and has now lost his seat in the Commons. It is not clear what he is going to do next.

And what about the prospect of an early General Election? While national polls suggest that Theresa May is doing well, the result - and the unpredictably of politics at the moment - is likely to strengthen the prime minister's resolve to wait until 2020 to call a General Election.

Of course, Liberal Democrats threw the kitchen sink, and more, at this by-election flooding the place with volunteers. They would not be able to do this at a General Election.

That said, while the Conservatives may fancy their chances in Labour-Conservative marginals, they will start to worry about former Liberal Democrat seats in places where people did vote remain and the risk that could pose.