Society is well aware of the danger posed by drivers who get behind the wheel while under the influence of alcohol.

Few of us pause to consider, however, that we might be sharing the roads with people high on drugs.

Worrying statistics from North Yorkshire Police show that we are indeed running the gauntlet of such folly.

In two months, officers have arrested 17 men and three women for being in charge of a vehicle while unfit to drive due to drugs.

Perhaps one of the most worrying aspects of drug-driving is the uncertainty that surrounds it.

Hallucinations, panic, paranoia, dizziness and confusion can all seize those who have been taking drugs, whether or not they get behind the wheel of a car - but when they are driving, they are in charge of a deadly weapon.

And as Inspector Dave Brown, North Yorkshire Police's new head of strategic roads policing, says the effects can last for hours or even days.

The case of 23-year-old drug-driver Suleman Majeed shows the consequences well.

Majeed was jailed for 18 months for causing a serious head-on crash in North Yorkshire while under the influence of cannabis and diazepam, and causing serious injury to the other driver.

He pleaded guilty to driving under the influence of drugs, dangerous driving, driving while disqualified and without insurance.

As well as his jail sentence, he received a six-year driving ban and will have to meet extremely strict conditions if he is ever to get his licence back.

We hope those arrested will face similarly stern justice if convicted - for their sakes, as well as for the sake of the others whose lives they put at risk.