Britain’s security services are to escape further scrutiny by parliament’s intelligence and security committee for their failure to prevent four terror attacks this year in which 36 people died.

The decision comes as the home secretary, Amber Rudd, gave her backing to an increased role for MI5 in tackling domestic extremism, including that carried out by rightwing terrorists and groups. MI5 already play an important role in combating Islamist terrorism.

A report on the performance of MI5 and counter-terror police published by David Anderson QC on Tuesday did not purport to provide independent scrutiny but instead “assessed the quality” of nine unpublished internal reviews into the services’ handling of intelligence.



Anderson concluded that “their investigative actions in all cases were for the most part sound” but did identify failings that meant it was “conceivable that the Manchester [Arena] attack in particular might have been avoided if the cards had fallen differently”.

Among other failings, the internal reviews established that the Manchester attacker, Salman Abedi, had been identified by “targeted data exploitation and other automated techniques” as one of a small number of individuals who merited further examination. A meeting to discuss them was scheduled for 31 May, but the attack at Manchester Arena happened on 22 May.

Critical headlines about the performance of the security services were overshadowed first by an MI5 statement disclosing that nine UK terror plots had been thwarted since March and later on Tuesday by the news that two suspects had been charged over an alleged plot to kill Theresa May.

The intelligence and security committee (ISC), which is parliament’s principle means of holding MI5, MI6 and GCHQ to account, has had no opportunity to examine this year’s terrorist attacks as it was only set up on 23 November after months of delay. Its chairman, Dominic Grieve, said after its first meeting since the election that consideration of the attacks would be the committee’s “top priority”.

But on Tuesday Grieve told MPs that “rather than just trying to reinvent the wheel in respect of what Mr Anderson has done, we will endeavour to maximise the efficiency of both services”. He said the ISC’s main focus in its independent inquiry should be on ensuring recommended changes “in the way in which the work of the counter-terrorism agencies and MI5 is linked in the sharing of intelligence.”

Further public scrutiny of whether the security services could have avoided the attacks will now take place through the formal inquest process, which is expected to be lengthy.

Rudd has however not ruled out a public inquiry if coroners believe they cannot deal with all the issues raised through the inquest process.

An increased role for MI5 in tackling domestic extremism was one of three major recommendations proposed by the security services.

The new approach is aimed at ensuring that equal weight is given in analysing and dealing with all kinds of terrorism, irrespective of the ideology that inspires them. The decision will mean that the joint terror analysis centre, which sets the national threat level, should include in its work an assessment of terrorist threats arising from domestic extremism.

In recent years controversy over the definition of domestic extremism has seen the police redefine it as “activity of groups or individuals who commit or plan serious criminal activity motivated by a political or ideological viewpoint”. This has included animal rights, environmental activists as well as far-right racists.

An ISC spokesperson said: “No decisions on the scope of the committee’s inquiry have yet been taken and the committee continues to closely scrutinise the Anderson report, as well as the MI5 and police internal reviews.”



