By Dan Whitworth
Newsbeat technology reporter
PCs Gareth James and Robbie Burns work for Chester police
Lives are being put at risk because of delays in getting roadside drug testing kits to police. That's according to road safety campaigners.
Instead officers say they're still checking drivers by getting them to do things like stand on one leg and walk in a straight line.
PCs Gareth James and Robbie Burns regularly patrol the roads around Chester looking for drink or drug-drivers.
With Newsbeat tagging along for the night, it's not long before they spot one guy driving without his lights on.
He's on his way home from a gig and the officers suspect he may have taken drugs.
They give him a field impairment test (FIT test), examining his eyes and testing things like his balance and co-ordination. This time he was let go.
But PC Robbie Burns says it's not always so straight forward.
"One of the worst examples that we dealt with was a delivery van that was totally chopped in half," said Robbie Burns.
"The driver was killed instantly. We later found out that the offending driver actually had amphetamines and cannabis in his system."
The victim was dad of two, Ron Birch. His wife Fiona says the impact on their family was horrendous.
She said: "He wasn't just my husband, he was my best friend, my soul mate.
"I just exist, instead of living."
Road safety campaigners say the FIT test isn't good enough and police need drug testing kits now.
But at the moment the law isn't about if drivers have drugs in their system.
It's about whether or not those drugs impair their ability to drive.
The drug testing kit is already being used in some EU countries
The Department of Transport has launched a review into whether the law needs changing.
Graham Sievers works for a British company, Concateno Plc, that makes and designs drug testing kits already being used in some European countries like Italy and Spain.
"Very simple to use. We get a saliva sample, placed into the handheld computer," he explained.
"That's analysed and within five minutes you get a result for six drugs."
The Home Office says it's still working on getting the technology right.
For now police will have to stick to Fit tests to check if people are drug-driving.