New legislation is needed to give police greater powers to investigate potential terrorist activity online, said the head of Northern Ireland’s specialist anti-terror unit.
Detective Superintendent Kevin Geddes said technology had overtaken current laws governing what data officers could and could not access to combat extremism.
The Scottish-born officer, who leads the PSNI’s Terrorism Investigation Unit (TIU), expressed fears of “going dark” on the online contacts between potential dissident republicans.
“Going dark is really when we lose the ability to see what’s happening communications-wise, and that’s a real challenge,” he said.
“Technology has overtaken the legislation we have, which prevents us from capturing how people communicate.”
The issue of beefing up legislation is extremely politically divisive.
Supporters of the move stress the need to make compromises with individual privacy to keep people safe, while opponents characterise it as a snoopers’ charter.
The Government introduced emergency legislation last year to ensure internet and phone companies retained their customers’ personal communications data.
But the law stopped short of including internet browsing histories in the face of Liberal Democratic opposition.
The emergency legislation will expire in 2016, requiring whatever government is in office next year to legislate again on the contentious issue.
Parliament is also considering law changes that would give police greater powers to access IP (internet protocol) addresses to identify specific devices using the net.
“Personally, and I know other people would say this as well, I think there is a real need for (new) legislation around the internet, the going dark,” said Mr Geddes.
He added: “With the internet and IP addresses and resolving IP addresses, it is less and less easy to do that and in fact in some cases it is practically impossible.
“So you lose the ability to work out the other pieces of the puzzle.”
The senior detective acknowledged the issue was not straightforward and said there was a need for a mature public debate.
“The balance is around privacy because the more you open the legislation potentially the less privacy people have and that’s always going to be the debate,” he said.
“So anything that would be done would have to be with oversight and the proper legislative process.
“But it’s an area I would have worked in for some time and communications data and capturing of communications data for policing purposes is becoming harder and harder and without new legislation it is going to be really difficult.
“New legislation would be really, really useful.”