Mum’s Latest Defence: GERD Claims to Explain High Breath Test Reading After Mercedes Flip
A Sydney mother, previously acquitted of a drink-driving charge after attributing a high breathalyser reading to a health supplement, is now presenting a new defence strategy. Natasha Jansen, 51, faces fresh charges following a dramatic incident where she flipped her Mercedes-Benz on Sydney’s lower north shore. Her latest explanation for an extremely high roadside alcohol reading involves gastro-oesophageal reflux disease (GERD), a condition she claims caused a false positive.
The incident occurred on August 29, less than three weeks after Jansen was cleared of her initial drink-driving offence. She was involved in a collision on Kameruka Road at Northbridge, where her luxury Mercedes veered off the road, struck two parked cars, and ended up on its side. Emergency services were called to the scene, and builders from a nearby construction site assisted in extricating Jansen from the wreckage.
At the scene, Jansen returned a positive result for alcohol. However, she subsequently refused to undergo a breath test at Chatswood police station. This refusal led to charges of negligent driving and failing to submit to a breath analysis. Further analysis of blood samples revealed the presence of delta-9-tetrahydrocannabinol (THC), the primary psychoactive compound in cannabis, in her system. Consequently, Jansen was hit with an additional charge of driving a vehicle with an illicit drug present in her blood.
Jansen, a mother of two and a former private school mum, initially made headlines in July 2024. She was charged with drink-driving after falling asleep at the wheel while parked outside her children’s school sports grounds, also in Northbridge. Her initial breath test reading was 0.243, followed by a second reading of 0.193 at the police station.
Her defence at that time, presented by solicitor Michael Bowe, was that a combination of her skincare routine and a reflux condition, coupled with a chlorophyll health tonic she had consumed, led to an inaccurately high breathalyser reading. Mr Bowe argued that the chlorophyll, available in liquid form from supermarkets, could have caused alcohol in her mouth to register falsely high.
Magistrate Margaret McGlynn accepted this explanation, noting that the breathalyser might have detected alcohol content in her mouth rather than her bloodstream. Evidence was presented that Jansen had consumed two 500ml bottles of liquid chlorophyll. Professor Macdonald Christie, a neuropharmacology expert, testified that this quantity should have resulted in a blood alcohol reading of 0.12 or lower, well below the high-range drink-driving threshold. Police breathalyser experts acknowledged that a reflux condition could indeed lead to inaccurate readings if it caused regurgitation into the mouth.
The court also reviewed police footage showing Jansen appearing steady on her feet and not exhibiting behaviour consistent with being five times over the legal alcohol limit. Jansen herself provided evidence that she was simply tired from a previous night of poor sleep. On these grounds, the drink-driving charge was dismissed on August 11 last year.
However, the legal troubles were far from over. Less than three weeks later, the August 29 incident occurred. In her latest court appearance on February 5, Jansen pleaded guilty to the three offences: negligent driving, failing to submit to a breath analysis, and driving with THC in her blood.
When she returned to Hornsby Local Court for sentencing on Thursday, Jansen used an umbrella to shield herself from media cameras. Her solicitor, Mr Bowe, informed Magistrate Michael O’Brien that while his client had pleaded guilty, she disputed certain aspects of the police statement of facts.
Specifically, Mr Bowe took issue with what he termed “superfluous matters” in the police statement, including the alleged initial roadside reading of 0.304 – more than six times the legal limit. He pointed out that Jansen was charged with refusing a breath test, not exceeding the legal limit, making the 0.304 reading irrelevant to any charge.
The core of Jansen’s current defence for the high roadside reading centres on her GERD diagnosis. Mr Bowe stated that her condition causes her to produce false alcohol readings on roadside breath-testing devices. He also objected to details in the police statement regarding the number of vehicles Jansen collided with and the assertion that her car rolled an “unknown number of times.”
A “disputed facts” hearing has been scheduled for July, where Mr Bowe intends to call Professor Macdonald Christie again. The expert is expected to reiterate his testimony regarding the potential for reflux conditions and health supplements to interfere with breath test results.
Court documents obtained by 7News revealed that Jansen has stated she has a “history of alcoholism, is unemployed and has two children as dependents.” Police, in their allegations, stated that Jansen “appears to have been intoxicated while driving a vehicle leading to a collision that by luck did not result in the injury/death to a person.” They further alleged that she “willingly failed to respond to legislated obligations placed upon her being the driver of a motor vehicle involved in a collision.”
Residents in the vicinity described the scene of the crash as dramatic, with one local telling 7News, “It was like a movie set to be honest. I heard that the car actually went airborne.”
As part of her bail conditions while awaiting sentencing, Jansen is prohibited from operating any motor vehicle or even sitting in the driver’s seat. In recent months, she has been observed being dropped off at her Northbridge home in a chauffeur-driven Kia Carnival and arriving at court accompanied by her father in a Lexus NX300, highlighting her reliance on others for transport.
