The newly passed Road Traffic Bill 2016 means that Gardai now have the powers to test drivers for drugs at the roadside.
Members of the Gardai can test drivers for cannabis, cocaine, a range of opiates, including heroin and morphine, and a range of benzodiazepines including diazepam and flurazepam.
The bill also enables local authorities to establish a special speed limit of 20km/h around housing estates and other built-up areas.