The controversy over the collapsed China spy case explained

The UK government is facing questions after a case against two men accused of spying for China collapsed just weeks before the trial was due to go ahead.

In September, prosecutors unexpectedly dropped the charges, sparking a political row over who was to blame.

The background to the case is complicated - so here we try and walk you through how we got here and the political impact.

Christopher Cash, a former parliamentary researcher, and Christopher Berry, an academic - who have both consistently maintained their innocence - were charged under the Official Secrets Act in April 2024.

They were accused of gathering and providing information prejudicial to the safety and interests of the state between December 2021 and February 2023.

The case against the pair alleges that they passed politically sensitive information to a Chinese intelligence agent, which was then handed to a senior member of the Chinese Communist Party. Both men deny the allegations.

The head of the Crown Prosecution Service (CPS) has said the case collapsed because evidence could not be obtained from the government referring to China as a national security threat.

Director of Public Prosecutions Stephen Parkinson, who is the most senior prosecutor in England and Wales, said the CPS had tried to obtain further evidence from the government "over many months" and that witness statements did not meet the threshold to prosecute.

He said that, while there was sufficient evidence when charges were originally brought against the two men in April 2024, a precedent set by another spying case earlier this year meant China would need to have been labelled a "threat to national security" at the time of the alleged offences.

However, some legal experts have questioned whether the CPS would have needed this evidence to go ahead with the prosecution.

Downing Street has insisted the decision to drop charges was made by the CPS, with no minister, member of government or special adviser involved.

The government has maintained that it is frustrated the trial collapsed.

Prime Minister Sir Keir Starmer has also sought to shift the focus to the previous Conservative government, which was in power when the alleged offences took place.

He argued the prosecution could only be based on the Tory government's position at that time, when he says China was not designated a "threat to national security".

Current Conservative leader Kemi Badenoch has rejected this, pointing to examples of Tory ministers and government documents describing China as a "threat".

A number of former senior security and legal officials have also questioned the government's argument.

The Tories have accused the government of refusing to give the CPS the evidence it needed to secure convictions.

They have suggested that the PM's national security adviser Jonathan Powell, who has sought closer relations with Beijing, may have intervened.

The government has insisted Powell, who is one of the PM's most senior advisers and political allies, was not involved in any decisions about the evidence provided in the case.

It says deputy national security adviser Matthew Collins, a civil servant, provided witness statements for the government - one in December 2023 under the Conservatives, and two further statements in February and August this year after Labour took office.

Security minister Dan Jarvis told MPs that Mr Collins was given "full freedom to provide evidence without interference" from ministers and special advisers, and that his evidence did not "materially change".

The government has now published the witness statements, following pressure from opposition parties.

In his witness statements, Mr Collins describes China as "the biggest state-based threat to the UK's economic security" and says the country's intelligence services "conduct large-scale espionage operations against the UK".

In his two statements submitted under Labour, he also emphasises that the government is "committed to pursuing a positive relationship with China".

His final statement from August adds: "The government's position is that we will co-operate where we can; compete where we need to; and challenge where we must, including on issues of national security."

The Conservatives have pointed to this language as being "directly lifted" from Labour's 2024 election manifesto and have questioned whether a government adviser or minister suggested it should be included. The government denies this.

The Tories have argued that it also undermines the government's insistence that the statements reflected the previous Conservative policy on China.

Government sources say Mr Collins was merely offering wider context about the government's approach to China and that all that mattered in the case was the Conservative position at the time of the alleged offences.

Meanwhile, critics of the CPS have suggested there was still sufficient evidence to put the case before a jury.

Badenoch has accused the government of deliberately collapsing the trial because "the prime minister wants to suck up to Beijing" - something it has denied.

Since last year's general election, Labour has sought closer trade ties with China to help achieve its aim of growing the economy.

Then-Foreign Secretary David Lammy, Chancellor Rachel Reeves and Mr Powell have all visited the country over the past year.

The government has insisted its approach to China is rooted in the UK's national interests.

However, Badenoch has claimed that, following the collapse of the case, it seemed the PM has been "too weak to stand up to Beijing on a crucial matter of national security".

The row puts further pressure on the government to harden its stance on China, potentially hindering its attempts to improve relations between the two countries.

The Chinese embassy in London has dismissed the case as "pure fabrication" and urged the UK to "stop hyping up anti-China narratives".

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