The government has published witness statements submitted by a senior official connected to the collapse of a trial involving two men accused of spying for China.

Here are three big questions that flow from them:

1. Why weren’t these statements enough for the Crown Prosecution Service (CPS) to carry on with the trial?

For this prosecution to go ahead, the CPS needed evidence that China was a “threat to national security”.

The deputy national security adviser Matthew Collins doesn’t explicitly use this form of words in his evidence. But he comes pretty close.

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In the February 2025 witness statement, he calls China “the biggest state-based threat to the UK’s economic security”.

Six months later, he says China’s espionage operations “harm the interests and security of the UK”.

Yes, he does quote the language of the Tory government at the time of the alleged offences, naming China as an “epoch-defining and systemic challenge”.

But he also provides examples of malicious cyber activity and the targeting of individuals in government during the two-year period that the alleged Chinese spies are said to have been operating.

In short, you can see why some MPs and ex-security chiefs are wondering why this wasn’t enough.

Former MI6 head Sir Richard Dearlove told Sky News this morning that “it seems to be there was enough” and added that the CPS could have called other witnesses – such as sitting intelligence directors – to back up the claim that China was a threat.

Expect the current director of public prosecutions (DPP) Stephen Parkinson to be called before MPs to answer all these questions.

2. Why didn’t the government give the CPS the extra evidence it needed?

The DPP, Stephen Parkinson, spoke to senior MPs yesterday and apparently told them he had 95% of the evidence he needed to bring the case.

The government has said it’s for the DPP to explain what that extra 5% was.

He’s already said the missing link was that he needed evidence to show China was a “threat to national security”, and the government did not give him that.

The newly published witness statements show they came close.

But if what was needed was that explicit form of words, why was the government reticent to jump through that hoop?

The defence from ministers is that the previous Conservative administration defined China as a “challenge”, rather than a “threat” (despite the numerous examples from the time of China being a threat).

The attack from the Tories is that Labour is seeking closer economic ties with China and so didn’t want to brand them an explicit threat.

3. Why do these statements contain current Labour policy?

Sir Keir Starmer says the key reason for the collapse of this trial is the position held by the previous Tory government on China.

But the witness statements from Matthew Collins do contain explicit references to current Labour policy. The most eye-catching is the final paragraph of the third witness statement provided by the Deputy National Security Adviser, where he quotes directly from Labour’s 2024 manifesto.

He writes: “It is important for me to emphasise… 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.”

Did these warmer words towards China influence the DPP’s decision to drop the case?

Why did Matthew Collins feel it so important to include this statement?

Was he simply covering his back by inserting the current government’s approach, or was he instructed to put this section in?

A complicated relationship

Everyone agrees that the UK-China relationship is a complicated one.

There is ample evidence to suggest that China poses a threat to the UK’s national security. But that doesn’t mean the government here shouldn’t try and work with the country economically and on issues like climate change.

It appears the multi-faceted nature of these links struggled to fit the legal specificity required to bring a successful prosecution.

But there are still plenty of questions about why the government and the CPS weren’t able or willing to do more to square these circles.