Opposition politicians are suing Boris Johnson for failing to investigate suspected Kremlin interference in to British politics.

MPs from the SNP, Labour and the Greens have teamed up with Liberal Democrat and cross-bench peers to argue that the prime minister broke human rights laws by not ensuring elections are free and fair. 

Their legal action - believed to be the first filed against a government for national security failures - is also designed to force Mr Johnson to put in place an “adequate legislative framework to protect against future foreign interference”.

It comes four months after the publication of the long delayed Russia Report, which found “credible evidence” that Vladimir Putin’s regime had targeted UK elections.

The report, by the Westminster Intelligence and Security Committee, also said the UK was “clearly a target for Russia’s disinformation campaigns and political influence operations’ and that the country “must therefore equip itself to counter such efforts”.

Read more: Why has Scotland failed to have an adult debate about the contents of the Russia Report?

Authorities in the United States have documented covert and overt efforts to support the populist presidential bid of Donald Trump in 2016. 

However, the UK has not had a similar inquiry in to whether - or even how - Mr Putin’s Russian government and its proxies backed British nationalists over Brexit in the same year.

The legal action personally names Mr Johnson, who led the official campaign for Brexit and who delayed the Russia Report until months after his 2019 general election victory. 

The MPs pursuing the judicial review against Mr Johnson are Alyn Smith of the SNP,  Ben Bradshaw and Chris Bryant of Labour and Caroline Lucas of the Greens. They are backed by Liberal Democrat peer Lord Strasburger and a former Tory, Baroness Wheatcroft. 

Mr Smith - along with other allies of First Minister Nicola Sturgeon - has long warned that the SNP has been under attack from the Kremlin.

In a witness statement backing the action, he said: “I believe the UK government has a case to answer over grave concerns Scotland’s and the UK’s democracy was subverted by external influence and illegal activity, and, that without further reforms, they remain vulnerable to further subversion by foreign hostile states.”

Speaking about the action, he added that said MPs had turned to the law because scrutiny could not come from parliament while the Tories had a “80-seat sycophant majority”. 

No Conservative has joined the action. However, former newspaper editor Baroness Wheatcroft, a Conservative peer until she lost the whip, said government failure to take action voluntarily was ‘shameful’ and that there was ‘no doubt that the internet has opened the way for widespread potential interference in the electoral process from malign forces and that Russia has tried to exploit that opportunity”. 

The legal action has secured a witness statement from Lord Peter Ricketts, a former chair of the Joint Intelligence Committee and the first ever National Security Advisor to the UK Government.

Lord Ricketts said he was surprised “the government appeared not to have sought evidence on whether the Russian state was successful in interfering in the 2016 EU referendum campaign, and neither had it made any post-referendum assessment of Russian attempts to influence elections in the UK”.

He continued:  "Given the importance of knowing the extent of past Russian interference in assessing the  risk  for  future  elections, I do  not  understand why the  Government  would choose  not  to investigate."

Read more: 'Russian actors' tried to interfere with 2019 General Election

Lord Ricketts was careful to blame politicians, not security services for not investigating. There was, he concluded, a “failure to give political direction”.

The thrust of the legal action is that the government has a legal responsibility to ensure elections are free from outside interference, under Article 3 of the European Convention on Human Rights.

Litigants mostly cite the Russia Report. However, they also refer to remarks by the foreign secretary, Dominic Raab, who talked of “online amplification of illicitly acquired and leaked Government documents” in the 2019 General Election.

Russia has been accused of several “hack and leak” operations around the world

This is when material is stolen before being published on the internet, often partially, and then framed in a negative light by state propaganda, anonymous online social media accounts and proxies.

The SNP has repeatedly warned about potential Kremlin attempts to meddle in Scotland’s independence debate. One of the first documented Russian influence operations in the UK was an attempt to spread false claims that the 2014  referendum was rigged. 

The legal action is backed by a not-for-profit called the Citizens.

A spokesperson for the group said: 'It is completely extraordinary that the UK government should have so little concern for the national security of the country, that a cross-party group of MPs and Peers feels it has no choice but to take legal action in this way. As far as we know, it is unprecedented in modern British history. In the US, multiple investigations involving hundreds of intelligence officers and Congressional inquiries have detailed the extensive attacks by Russia on the 2016 US election. In Britain, that process hasn't even begun. We hope this will be the beginning of the beginning of that process.”

A UK Government spokesman declined to comment on ongoing legal proceedings.

But he said: "Safeguarding our democracy will always be an absolute priority and the UK has robust systems in place to protect our elections and institutions from interference.

“To prevent against any future threats we are bringing forward new legislation to provide the security services and law enforcement agencies with the tools they need to disrupt hostile state activity.

"And we have also published proposals for a digital imprint regime that will improve transparency in political campaigning online, and are developing an online media literacy strategy to help empower the public to question the information they read online."