Online evidence may be used to lock up freed paramilitaries in Northern Ireland
Intercept evidence could be used to recall former paramilitary prisoners to jail in Northern Ireland, the UK's terrorism watchdog has said.
IRA and loyalist inmates were released early during the peace process but sentences can be reinstated by the Government if further offences occur.
Ministers in Britain want new laws to help police and agencies monitor online threats, and terrorism powers reviewer David Anderson QC recommended additional measures to protect the public be considered.
The evidence would include the interception of emails, internet conversations and phone calls.
The Northern Ireland Office (NIO) said the Government would be considering his report carefully.
Mr Anderson said: "It is not the function of this review to second-guess or to reinforce the eight reviews which have, since 1993, failed to recommend that intercepted material be rendered admissible as evidence in court.
"I do however recommend that consideration should be given to extending the already substantial list of exceptions from this rule to include the Parole Commissioners and Sentence Review Commissioners, both in Northern Ireland.
"There would be a possible benefit in terms of public safety: these bodies consider prisoner licence cases and have the ability to consider classified material in closed proceedings on the issue of whether persons convicted of serious offences remain a threat to the public.
"Allowing intercept to be admitted as evidence before them could enable the recall to prison of ex-prisoners on licence in respect of whom the evidence of continuing threat to the community comes from intercepted communications."
Paramilitary prisoners were released early under the 1998 Good Friday Agreement which largely ended the 30-year conflict. However, there have been 24 recalls of individuals back to prison, ordered by Northern Ireland secretaries.
The secretary of state can suspend - recall an individual back to prison - the licence of anyone released under the Northern Ireland (Sentences) Act 1998 on the basis of information which indicates they are in breach of the conditions of the licence.
If a licence is suspended it will be for the independent Sentence Review Commissioners (SRC) to review the case and determine whether to revoke or reinstate the it.
High-profile offenders to be returned to jail include notorious loyalist killer Torrens Knight, who was jailed for the 1993 Greysteel massacre.
He was released in 2000, but jailed again in 2009 for assault.
Mr Anderson has said new laws were needed to cover security services' powers to monitor online activity.
- UFF killer Torrens Knight was given 12 life sentences for the Greysteel massacre and the murder of four workmen in Castlerock. He was released under the Good Friday Agreement in 2000, but jailed in 2009 for assaulting two sisters in a Coleraine bar.