Last May in Portlaoise prison, James Cahill’s nerve finally snapped. The bars and high walls of the high-security jail no longer seemed to offer the convicted hitman enough protection from his previous employers: the Dundon-McCarthy gang that controls drugs in the west of Ireland.

The Birmingham criminal had been warned that he was now more a liability than an asset. He approached prison staff saying he wanted to talk to gardai. When detectives visited, Cahill asked for a deal: “Transfer me to safety, get me into the Witness Security Programme (WSP) and I’ll confess and name the others involved.”

Detectives couldn’t believe their luck. Cahill was put in solitary confinement and given round-the-clock protection. “He blew the whole scene wide open,” said one of the detectives involved in the investigation.

Several drug dealers in the west of Ireland, and some of their key enforcers, were implicated by Cahill’s confession. The biggest murder investigation in the history of the state, involving more than 80 officers, was cracked open. At least six files were prepared for the director of public prosecutions (DPP).

But will Cahill ever get the opportunity to stand up in a courtroom and point at some of Limerick’s leading gangsters in the dock? Gardai believe the DPP is awaiting a Supreme Court judgment in the case of John Gilligan before deciding how to proceed.

So should supergrass evidence from the likes of Cahill be admissible? And if not, how else will gardai catch and convict the growing number of trigger-happy drug barons, who shot dead three people in Dublin last week alone?

AN unmarked garda special branch car pulled alongside a silver Peugeot 306 in west Dublin on the night of March 21, 2003. Gardai had been following the Peugeot driver — Cahill — for half an hour and finally decided to make their move.

The detective on the passenger side put his badge to the window and signalled Cahill to slow down. Instead the Peugeot swerved into the unmarked squad car.

The chase ended a kilometre later with the Peugeot, stolen five weeks earlier in Armagh, trapped against a wall at the Citywest complex. In a bag on the seat beside Cahill, detectives found a disassembled Uzi sub-machinegun and 15 rounds of ammunition.

Cahill was on the way to “work”. He had been paid by the Continuity IRA to kill Declan Griffin, a Dublin drug dealer. In a sign of how cheap life has become in gangland, Griffin was dead within a fortnight, shot in the back of the head as he sipped his drink in the Horse and Jockey pub in Inchicore.

Four months earlier Cahill had executed Brian Fitzgerald, a Limerick bouncer who refused to let dealers peddle drugs in Doc’s nightclub in Limerick. Fitzgerald’s murder cost the gang a mere €10,000.

Last weekend as Dublin erupted in gang warfare and the blood of three feuding drug dealers was spilt in as many days, Cahill pleaded guilty to Fitzgerald’s murder and was given a life sentence. But he made it clear that he was willing to give evidence about who paid for Fitzgerald’s killing. He told the judge: “What I am trying to say is that I will testify against people. That’s why I feel my life is in danger.”

The next day the garda commissioner established a 50-man specialist unit to crack down on gangs. But conviction rates for gangland crimes are rock-bottom and the gardai’s main tactic is the use of supergrass evidence.

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