End of the road for 'drugged up' drivers

Hey this will throw the Cat among the Pigeons, I just got in the Email the News Letter from the RAC , WA. and I say , The more checks they do the better. And is Ben one of the first victims, if he is then good, but a shame to see a young man fall of the top rung of the ladder in such a way,

For too long drug users have put other motorists' lives in jeopardy.
They have driven whilst under the influence of illicit drugs with little fear of being caught. But October marks the end of the road for drugged up drivers.Roadside drug testing is now a reality across Western Australia.
WA police have been armed with kits which test for THC (the active ingredient in cannabis), methylamphetamine (‘speed' and ‘ice') and MDMA (‘ecstasy').
Drug tests will be carried out from the new Alcohol and Drug Buses. Individual roadside checks can also be carried out by officers who suspect a driver is under the influence of drugs.
After a driver is stopped, an initial saliva swab will be taken and screened. If the test is positive the driver will need to provide a second sample in the bus or they may be taken to another test facility.
THC can be detected in saliva for around four hours after use, while methylamphetamine can be detected for around 24 hours. However, the length of time that traces of each drug are detectable will vary depending on the dose and the individual's metabolism. Last year in WA, 25% of drivers involved in road fatalities showed traces of one or more illicit drugs in their blood.