By John Ware
BBC Panorama Reporter, Analysis
Panorama's John Ware examined intercepts in the Omagh bombing
The government's decision to shelve plans to lift the ban on intercept as evidence in criminal trials follows a familiar pattern.
There have been no less than seven reviews in the last 15 years. Each one began with a prime minister saying: "Let's look at this". And with good reason.
Britain is the only country in the developed world not to allow intercepts from telephones or e-mails to be admissible in court, even though they may contain clinching evidence of a defendant's guilt.
Supporters of the ban being lifted say there is nothing quite as powerful as a suspect being confronted with his own incriminating words.
When the former Director of Public Prosecutions Sir Ken MacDonald looked at how the Australian Police used intercept, he was told any jurisdiction not using it in court wasn't "serious about crime". Intercept was, he added, the "best single weapon available".
And yet in the UK, each government review - including the one that has just reported back - has ended with a delegation going back to the prime minister saying: "Sorry, we've looked at it. It can't be done."
Why is this?
When Gordon Brown became prime minister he set up a privy council review under Sir John Chilcot, now head of the Iraq inquiry.
In February 2008, Sir John recommended limited disclosure in some trials provided nine separate conditions could be met. Most gave the intelligence services a veto in one form or another.
However, Gordon Brown asked a special implementation team to see if the conditions could be met. Following a series of mock trials, that team has reported back to say they cannot.
The UK makes extensive use of intercept to help law enforcement agencies and customs prevent crime and to provide them with leads.
Phone conversations can be intercepted but not used in court
According to Sir John Chilcot, our use of intercept as an intelligence gathering tool is as extensive as it is in America, despite the US population being five times greater.
The difference is that America and other countries with legal systems similar to ours also use intercept to gather evidence to help secure convictions.
It is tempting to then ask: Is there something about British crime that is so different from other countries? If not, then what's going on?
In the past, opposition has come mainly from the intelligence agencies concerned that intercept methodology and technology will be compromised.
Supporters of the ban being lifted, including Sir Ken MacDonald, respond by saying: "Is there really something about British intercept technology that is so much better than all the other developed countries in the world, including the USA?".
Human rights issue
It seems unlikely.
Yet opposition from the intelligence agencies continues. GCHQ in particular is said to be "fundamentalist" on the matter.
In addition to their concerns over protecting methodology and technology, the government had added worries over human rights - or at least the way European laws are interpreted in British courts.
The mock trials conducted to test proposals to allow some use of intercepts have apparently shown that our adversarial system cannot be squared with our human rights obligations of full disclosure to the defence.
And yet those obligations have not been raised as an obstacle even by Liberty's Shami Chakrabarti, a strong supporter of the intercept ban being lifted.
Sceptics of government's decision to retain the ban chide that it is the first time the Home Office has said human rights should trump all other considerations.
"It was always obvious that Chilcot's preconditions for lifting the ban were never going to be fulfilled," said a former senior official in the Crown Prosecution Service.
On the other hand, Lord Carlile, the government's independent reviewer of terrorist legislation, said the burden on the prosecution to disclose to the defence is much more onerous here than in any other country, Europe included.
Intelligence services say they need to keep their methods a secret
The government has concluded that the combination of our liberal disclosure regime and the fact that we use intercept so extensively means there is no workable way of storing the voluminous phone tap and e-mail traffic recorded by the intelligence services and law enforcement agencies.
The government has said it will continue the search for a workable regime. However, if the ban is ever lifted it is likely to apply - at least at first - only to non-terrorism criminal cases.
Lord Carlile says that for the intelligence services to administer a disclosure regime would be especially burdensome, diverting their resources from carrying out their main task which is to interdict terrorists.
Expect yet more reviews in the future.