A bus driver charged with driving while impaired by cannabis has a case to answer, a magistrate has ruled.

Belterre Swan, 55, has denied driving a vehicle while her ability to drive was impaired by a drug.

She also denies driving without due care and attention, or without reasonable consideration for others, in relation to a March 11 crash.

At about 11.30am that day, Mrs Swan was driving the number 8 bus along East Broadway when the vehicle struck a row of parked cars and a utility pole outside Great Things.

After the crash, she told investigators that her steering wheel had locked.

However, lab tests later discovered THC metabolites — chemicals formed when the body processes the active ingredient in cannabis — in her blood.

As the Magistrates’ Court trial continued yesterday, defence lawyer Larry Mussenden submitted that there was no case for Mrs Swan to answer, arguing that the Crown had presented no evidence that Mrs Swan knew she had consumed cannabis.

“You have to take into account what the defendant knew,” he said. “In this case if the defendant knew she had drugs in her system.”

He suggested she could have been exposed unknowingly to the drug in what he described as a “gas chamber” without knowing it.

“Just because you are in a room and it’s filled with smoke doesn’t mean you know it’s cannabis,” he added.

However, prosecutor Loxly Ricketts argued that, as with other traffic offences, it was not required that the Crown prove Mrs Swan knew she had cannabis in her system.

He also said that even if the courts found that knowledge was necessary, there was already evidence before the court that she knew.

While a prosecution witness had told the court that a “contact high” would result in up to 15 nanograms of metabolite per millilitre of blood, Mr Ricketts said the level in Mrs Swan system had been more than double that.

“The only reasonable inference would be that she ingested it,” he said.

“Smoked it, knowing that she was taking it in, not through a contact high as she is suggesting.”

After hearing both sides on the matter, magistrate Archibald Warner found that there was a case to answer on both charges and that the trial should continue.

• It is The Royal Gazette’s policy not to allow comments on stories regarding criminal court cases. As we are legally liable for any slanderous or defamatory comments made on our website, this move is for our protection as well as that of our readers.