'How the state tried to silence my abusive agent expose' - BBC News
BBC News reporter Daniel De Simone on his courtroom fight to reveal how an MI5 agent abused women.
Much of the evidence was kept secret from Daniel De Simone and the BBC team

No journalist enjoys attempts at censorship. We often face restrictions, but I had never encountered anything like this - a vast list of things the government wanted to ban me saying about an abusive MI5 agent I had spent a long time investigating.

I received the list during the months-long legal battle between the BBC and the government. I had been investigating a state informant for some time, and when we put the findings to the government, they took us to court. It eventually ran to 54 pages and included a series of arguments about the government's demands. They wanted to stop our story about the agent who can only be referred to as X.

The right-wing extremist had used his security service role to terrorise and coerce his British girlfriend, who we are calling Beth. In one incident, which she recorded on her mobile phone, he attacked her with a machete. Evidence we gathered establishes he had also threatened to kill women and children, and was a sexual threat to young girls.

I was the main witness in the legal case to defend reporting on the story. The litigation process took over my life. The pressure was significant and I had many low moments. My journalism was under scrutiny - with government lawyers critically examining every detail in the large volume of evidence, and challenging the accuracy of our work.

We argued that it was important to identify X so that other women he encountered could be warned about him and the abusive behaviour our investigation had uncovered. The security service, however, argued that naming X would create an unacceptable danger to him from extremists and discourage other people from acting as informants, which would damage national security.

The government initially asked for the right to exercise written approval over our reporting. This would have amounted to ministers having editorial control over our story, which we argued in court would be "repugnant" to any media organisation but particularly the BBC, with its charter obligation of independence from government.

This demand was eventually dropped and the judge later said he would have required "great persuasion" to have granted it.

This is the story of a dangerous MI5 agent, which the government tried to keep secret.

There were several stages to the court case. In one, the judge ruled - after receiving secret evidence that I was not allowed to see - that X could not be identified.

The next stage involved an argument over what other details should be kept from the public. I thought even if X was anonymised, our news report could still reveal a great deal and generate public debate about important issues, particularly the state's response to violence against women and girls. But it was clear that everything we had uncovered could potentially be censored.

Very little had been agreed between the parties, the judge noted, and the number of issues in dispute was "dispiritingly large".

The BBC's legal team outside the High Court in London

As he put it, MI5 was seeking to limit "practically everything known about [X] that is not already in the public domain". That was an awful lot, given the only things known publicly had emerged from the court case itself.

However, after receiving a judgement in the case this week, we were able to broadcast and publish a significant report on Thursday.

The legal case itself had been draining, with much of the evidence entirely secret and kept from me and the BBC team.

I was anonymous in the proceedings, but I cannot tell you why. My name was redacted in public documents, and when I was pointed at and referred to in open court - even when I was actually sitting there - my name was not used.

There was a challenge from MI5 on the reliability of the story, but the judge ultimately found I had taken "proper steps to assess whether its various elements were true" and that it was "comfortably" shown to have a credible evidential foundation.

The investigation had been lengthy and complicated. It started simply with the account of Beth and went from there. Eventually we found another abused former partner of X's - who, in our reporting, we called Ruth. Everything that could be, was tested and corroborated, with every new discovery subjected to the same process. The research would ultimately drag in MI5, the government, a foreign intelligence agency, police, prosecutors, and the High Court.

Hardly anyone within the BBC knew what was going on.

The whole thing felt like a parody of a spy film. I would sneak off from my normal tasks to carry out research and have meetings in odd locations. The small BBC team involved - investigations editor Ed Campbell, producer Sira Thierij and lawyer Lucy Moorman - used a random codename for the project and each element of the investigation was meticulously planned.

During the legal proceedings, my main opposite number was a senior MI5 officer, who could only be referred to as Witness A. On various issues, it was my evidence against his.

But the case involved another bewildering element.

The government had applied for something called a closed material procedure, where secret evidence is put before a judge, including during a closed hearing in a secure courtroom behind locked doors. This part of the case excluded the BBC team and our lawyers, with what are known as special advocates - security cleared barristers - appointed to act on our behalf.

The procedure is designed to let the security and intelligence agencies present evidence that is too secret for almost anyone to hear. I've reported on cases involving terrorism suspects where this process is central. But I effectively now found myself in the same position - blind to the evidence being presented against me. It will remain secret.

We met our special advocates and explained our case. However, once they had seen the secret evidence we were banned from communicating with them.

This meant we could not provide any instructions in response to the evidence they were seeing. Any further messages between us had to be channelled through an official go-between - a civil servant - to check that nothing secret was being disclosed. In court we could nod and smile at them, but have no conversations.

The two women we interviewed both think X could kill a woman - and I formed the same view.

Counter terrorism investigations are typically focused on preventing harm. Why wait for a terrorist to hurt people if you can stop him before? The same principle applied to investigating and challenging X.

The judge eventually ruled that we were allowed to publish and broadcast the story, and it came as a huge relief to finally be out there reporting on it so prominently. Since it went into the public domain on Thursday, it's led to the issues being debated and the story being referenced by leading politicians. One described the revelations as "harrowing and horrific" - the deputy prime minister, whose government had taken me and the BBC to court.

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