Hopeless Brexit planning has left Britain at risk from a new wave of terrorists

The twin threat of far-right extremists and Isis-inspired attackers can only be addressed with robust coordination across the continent

Largely unnoticed in the 2018 political chaos was a House of Commons Home Affairs Committee report on the security consequences of Brexit. In deeply concerned tones, the committee concluded that the government had not prepared sufficiently for the potential domestic security implications of Britain's departure from the EU.

Against a backdrop of lone actor plots across the continent and growing right-wing extremism, this is not good enough. The terror threat remains as diffuse and transnational as ever.

Key to disrupting these threats is information sharing – something the committee specifically identifies as at risk from the current approach to Brexit. The Police Federation, which represents 120,000 rank-and-file officers, claimed the government has left it with "no idea" how they will protect the British public after Brexit.

Recent plots in Strasbourg, Manchester, Bottrop, Tokyo, Sweden, Italy and Newcastle have repeated a pattern of lone individuals potentially, but not necessarily, linked to larger networks. They are hard to identify before an attack. They pop up across the continent and can occasionally get through, as was the case at the Strasbourg Christmas market.

In almost every case, investigations reveal the attackers were previously known to authorities. The positive we can draw from the larger picture is that a growing number are disrupted before the plot is enacted. The tough task for European authorities is to work out which of the many individuals monitored are genuinely prepared to commit murder.

To arrest them all would be vastly disproportionate. These individuals remain free not due to the authorities’ laxity, but rather because of a lack of evidence, or lack of guilt. Some will likely never become priority targets for authorities, or active terrorists.

So how do we keep improving the decision-making about who to focus on? In brief, we need a fuller understanding of the individuals, and that comes from gaining access to more data. The current arrangements around Brexit put that under threat. According to the government’s own figures, one database, the Second Generation Schengen Information System (SIS II), contains 76.5m records that were checked by UK enforcement more than 500m times last year.

In his evidence to the committee, deputy assistant commissioner of the Metropolitan Police Richard Martin highlighted the role of the European Criminal Records Information System (ECRIS). Martin quoted research that suggested “losing access to ECRIS would mean a response to a request about a foreign national’s criminal history would take an average of 66 days, compared to 10 days under ECRIS”.

At the same time as the threat from Isis-inspired terrorism has continued – despite talk of its "defeat" in Syria – we have seen a rise in extreme right-wing terrorism.

According to the 2018 Global Terrorism Index, right-wing groups and individuals killed 66 people in western Europe and north America between 2013 and 2017. In the UK alone the index tracked 12 far-right terror attacks in 2017, including the attack outside Finsbury Park mosque, where 47-year-old Darren Osborne drove a van into Muslim worshippers, killing one person and injuring at least nine others.

Perhaps most worrying are the potential links across Europe, where a more organised extreme right wing has long been visible in parts of Germany and is connecting across the continent. Groups in Central and Eastern European are making links to like-minded people in the UK, creating the alarming spectre of a transnational community.

Again, the only legitimate way to address this problem is closer connectivity and cooperation. Continental security partners will of course want to continue sharing information to counter a common threat, but in the absence of robust procedures and structures, information may slip through. It is all very good for security forces to want to share information, but this can only be done properly through appropriate and legally monitored channels to prevent abuse and protect civil liberties.

The combined threat of hard-to-track Isis sympathisers and international collaboration between far-right extremists present a relentless challenge to our security forces. They have had considerable success, but this is in part thanks to the shared information which builds difficult investigations to disrupt potential terrorists.

It is essential that they have the data to continue this task. Hard Brexit, soft Brexit or no Brexit at all, serious and concerted plans must be made to guarantee the seamless continuation of pan-European intelligence on the people that seek to do us harm. That there remains a lack of clarity here, despite expressions of concern by senior security officials, is a very worrying state of affairs.

Raffaello Pantucci is director of international security studies at the Royal United Services Institute for Defence and Security Studies (RUSI)