LIMERICK criminals didn't know it, but a grubby tennis ball in the corner of the small back garden of one of their houses contained a listening device that was secretly monitoring their meetings.
Ironically, the device was placed in the garden because the criminals had stopped discussing their business inside the house for fear of being bugged. Like most other organised criminals, they had long since stopped talking over the phone.
Gardai first surveyed the garden during a "routine" early morning raid and arrest operation. They noted the discarded ball among the general mess in the garden and had an identical replacement made.
The work and equipment used by the Garda's National Surveillance Unit (NSU) is, naturally, highly secretive. But it is also highly regulated.
Under the 2009 Criminal Law (Surveillance) Act, an officer of superintendent rank or higher must swear an oath before a district judge that he wishes to carry out electronic surveillance and that he believes the subject to be involved in the commission of an arrestable offence.
The "Information for an Authorisation" form which the superintendent swears before the judge contains a long list of detail – the who, why, what, where, when – of the criminal target and the intended operation. The judge can give permission for surveillance lasting up to three months. He or she can also refuse permission or set much stricter time limits, as gardai say, they regularly do.
The oath document is two pages long and the senior officer has to give quite considerable detail of the intended operation. Senior military officers and senior Revenue Commissioners are also covered by the same act. They must swear the same oath if they seek to spy on people for suspected threats to the security of the State or revenue offences.
The Surveillance Act came into being as the Government's response to escalating gang violence in Limerick, particularly the murder of the innocent rugby captain Shane Geoghegan. Beforehand, gardai carried out electronic surveillance under the 1993 Postal Packages and Telecommunications Act but could not use any information obtained in court; the 2009 Act allowed this for the first time.
The new act also contained safeguards to prevent the misuse of surveillance. A person who believes they are wrongly placed under surveillance can apply to an independent 'referee' – a district judge – and have their case examined. If it is deemed that guidelines were breached, compensation can be paid.
The legislation is designed to prevent gardai, or Military Intelligence or the Revenue Commissioners, from carrying out fishing expeditions. This is why they must convince and swear before the District Court.
The act also carries penalties for the unlawful disclosure of information obtained as a result of surveillance, up to five years' imprisonment and/or a fine of up to €50,000.
The Surveillance Act was welcomed by gardai, who for years had sought to be allowed to use such evidence in court.
It allowed gardai in Galway city to carry out 110 days of surveillance on a gang led by bothers Eddie and Michael O'Loughlin. And in June 2012, Eddie, 30, and Michael O'Loughlin, 34, were sentenced to nine years' imprisonment for directing organised crime.
In the case of the Limerick gang and the tennis ball, witnesses helped place most of this gang behind bars and the information obtained from the evesdropping operation was not used in court.
The gardai's use of the Surveillance Act for eavesdropping increased "three-fold" between 2010 and 2012, according to the annual report by the High Court judge assigned to review the use of the act. But no exact figures are given other than "less than 100" warrants were issued under Section 8 of the act, the section covering tracking devices.
The Defence Forces did not make any applications in 2012.
The Revenue applied to use tracking devices, presumably in smuggling investigations by Customs, on a "relatively limited" number of occasions.
The operation with the tennis ball in Limerick was, they say, quite unusual.
Much of the NSU's work is directed towards dissident republicans on behalf of the Garda Special Branch.
While reference was made last week to a "secret service", this exists only in the form of a fund agreed by government for the payment of informants and for providing funds for State witnesses in major cases.
The total budget of around a €1m has been underspent in recent years.