Covert surveillance, including phone tapping, is an important part of the fight against crime and, because it tests the boundaries of our rights, it is important that investigators try to strike a balance between privacy and law enforcement. The only public accounting for their activities is the annual report to the Legislative Council by the watchdog on legalised snooping – the Commissioner on Interception of Communications and Surveillance. The commissioner, Azizul Suffiad, has reported that last year police and other agencies obtained 1,378 authorisations for surveillance, about the same as the previous year. The number of operations that flouted the rules, or failed to comply with the terms of authorisations set by panel judges who issued them, was only 27. This is a seemingly insignificant number – except that it is a rise of 50 per cent from 18 the previous year. Worryingly this is a continuing trend. Such breaches have increased by 300 per cent from nine in 2015. It is good, therefore, to hear from the commissioner that the surge in irregularities, which included failure to stop eavesdropping on conversations involving confidential legal material, was down to inadvertent actions or carelessness, rather than deliberate acts. On the other hand, 13 years after passage of a law to put covert surveillance on a proper legal footing, it seems reasonable to expect that experience would have taught officers to be more diligent in exercising very sensitive powers. After all, the legislation was, at the time, very controversial, and only passed after a marathon four-day debate during which officials rejected numerous amendments that pro-democracy lawmakers claimed would better protect rights. In his previous annual report, Suffiad called for stepped-up training of covert surveillance operatives in compliance with judicial authorisations. It seems that if senior law enforcement officials paid heed, it has yet to make a difference. If last year’s increase in non-compliance continues, the number of breaches this year could exceed 40, and next year 60. For the sake of confidence in the use of the snooping law to fight crime, the authorities should redouble their efforts to ensure that operatives understand and comply with the boundaries of an intrusive arm of enforcement.