The US state of Colorado has signed new legislation requiring law enforcement officers to offer a breathalyser test to all drivers involved in collisions where a person is killed or seriously injured, after a promising junior cyclist was killed by a driver later found to have been drinking.
Magnus White was a promising cyclist who raced for both the US cyclo-cross and mountain bike teams. The 17-year-old was killed in 2022 when he was hit by a driver whilst on a training ride in Boulder, but the driver was never made to take a breathalyser test. Yeva Smilianska subsequently pleaded not guilty to a charge of vehicular homicide by reckless driving.
However, Smilianska was later revealed to have been drinking on the morning of the collision and had barely slept. She was subsequently found guilty in a trial that only concluded last April, and was sentenced to four years in prison.
White’s family believed the lack of an offered breathalyser test delayed the legal proceedings due to the time and effort taken to gather evidence of Smilianska’s fitness (or lack thereof) to drive. Speaking to CBS News, Magnus’ father Michael said: “In our case, 20 months. or in many other cases, [families] don’t get the truth ever. They don’t get the real reason why their loved one is dead.”
“We knew that we wanted to figure out how to get to the truth faster,” said Jill White, Magnus’ mother. “We felt like if this law was in place when Magnus was hit, it could have been a different line of events.”

Magnus’ Law does not penalise drivers who refuse the breathalyser test but can present a key piece of evidence that speeds up legal procedures. It will come into effect later this year.
The law differs from legislation in the UK, where police can stop and request to breathalyse road users at any time if they suspect a driver has been drinking, committed a traffic offence, or been involved in a collision. Failure to comply with the law could result in arrest.
> Promising teenage cyclist killed after being hit by driver just days before World Championships
Micheal White, Magnus’ father and Co-Founder of The White Line said “had this protocol for mandatory chemical testing existed in 2023, the driver who killed our son would have been properly tests. Critical evidence would have never been lost.
“SB25-281 recognises that these crashes are not ‘accidents’, they are crimes. They are the result of deliberate choices to drink, to use drugs, and get behind the wheel. Testing drivers is essential to saving lives and preventing incomplete investigations.”
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Since White’s death, his family have established The White Line charity which campaigns for further road safety measures, inspired by Magnus’ death. These include mandating automatic emergency braking on all newly sold cars, and successfully campaigning for Colorado statutes to replace the word ‘accident’ with ‘crashes’ when describing collisions.
The charity is aiming for a culture where careless and reckless behaviour becomes unacceptable by 2035. They say that they’re “here to transform driver behaviour now and make out streets safer today. The urgency of this cause demands nothing less.”
The bill was signed into law by Gov. Jared Polis while surrounded by cyclists at Valmont Bike Park in Boulder, which is a place Magnus is reported to have loved.
“The White family has really rallied and taken action to make sure fewer parents have to grieve their children,” Polis said. “It’s officially the law of Colorado.”

7 thoughts on “American cyclist’s death sparks law change mandating police to offer a breathalyser test to all drivers involved in serious collisions”
Totally absurd that you can be involved in a serious accident and not be required to prove you weren’t drunk
MURICA
Magnus’ Law does not penalise drivers who refuse the breathalyser…
legislation in the UK, where police can stop and request to breathalyse road users at any time if they suspect a driver has been drinking, committed a traffic offence, or been involved in a collision…
‘Offered’ a breathalyser! Note the ‘can’ described in the UK legislation, and I suspect that dodge is deployed more often by the police than many suspect
I can only give you my experience as a member of another blue light service in Essex. I see every driver involved in a collision where the police attend being breathalysed regardless of who is at fault. The only exception is where they are in no state to be tested and then I believe a blood sample is requested from the hospital. It’s been that way for a number of years.
As far as I understand the article, the driver in Magnus’ case wasn’t offered a breathalyzer, with the new law she would have been but she could refuse it without any penalty. I know the parents are saying it will accelerate the legal process in terms of providing evidence of the suspect’s fitness to drive but that presumably is only if they agree to be tested, which clearly if they know they will fail they won’t. What am I missing?
The US has a poor record on road safety. South Carolina has the worst record of all, with significantly more fatal crashes/head of population annually (around 23/100,000 of population) than is the average for Africa and about 10x the rate that we have in the UK. Even California, one of the safer states to drive in the US has around 4x the rate of annual deaths/100,000 of population of the UK.
It is shocking that police in the US still have to rely on archaic ability tests like making suspects walk in a straight line or stand on one leg to test for DUI. Breath testing was introduced in the UK in the 1960s while Australia led the field with saliva tests to check for drug use 20 years ago. The technology is proven. And yet US police officers are not allowed to do random stops of drivers as here in Europe.
Law in the US is preposterous and beyond comprehension . It should be mandatory in any collision
It’s a completely tragic incident that occurred to him unfortunately and there is a definite need for drivers of vehicles to be tested following such a horrific incident! I fully understand as I was an amateur racing cyclist struck horrendously bad by two different drivers under the influence of substances who should have never been on the road at that time. There needs to be action taken to better protect cyclists!