The Government’s chief legal adviser has denied that the collapse of the Chinese spying trial was “farcical” or a “mistake”. Attorney General Lord Richard Hermer told Parliament’s Joint Committee on the National Security Strategy: “It is a little easy to kind of jump to conclusions that may prove to be unfair.”

Lord Hermer, a barrister and Labour politician, said there had been a “mismatch” in the evidence needed to pursue the case, but said: “Now I don’t think that mismatch need be categorised as a mistake or farcical. You’re absolutely right to be looking at it, but I wouldn’t rush to say that. These are all people working incredibly hard to try and get this prosecution over the line.”

Lord Hermer is giving evidence to a parliamentary inquiry asking why a case against two men who had been accused of spying for China collapsed just weeks before the trial was due to go ahead.

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

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

Lord Hermer said “one very significant problem” affecting the alleged China spying case was the Official Secrets Act itself, which was “not fit for purpose”.

If updated legislation had been in place at the time of the alleged offending, the Attorney General said he had “no doubt” the prosecution would have gone to trial.

He told the Joint Committee on the National Security Strategy: “Standing back in this case, where’s the problem? What is it, because I think we should all be concerned to try and identify what lessons can be learnt.

“I’m clear in my mind that certainly one very significant problem here was the Act. The Act wasn’t fit for purpose, it was out of date.”

Lord Hermer said that in 2017, the Law Commission flagged that the term “enemy” was “deeply problematic” and “would give rise to difficulties in future prosecutions”.

“I think what has played out in this poros exemplifies and highlights the difficulties with that term,” he said.

He said Parliament was right to pass the National Security Act 2023 that takes away problems faced by prosecutors in the case and means it merely needs to be proved that “information was being passed to a foreign power”.

“Speaking frankly, I don’t understand why it took Parliament so long to pass that. Had that Act been in force at the relevant time for this case, between ’21-’23, I have no doubt that the prosecution would have proceeded to trial.”

Lord Hermer said the Crown Prosecution Service had been working in “good faith” to try to bring the Chinese spying allegations to court.

“These are people who are working in good faith to try and get this case into court,” the Attorney General told the Joint Committee on National Security Strategy.

He said: “Everything that I have seen shows me that this was a prosecution service working hard to try and secure a conviction.”