The Immediate Roadside Prohibition has been a feature of British Columbia traffic law for several years. Immediate Roadside Prohibitions are issued by police officers who claim that a driver blew into a screening device which returned a fail reading, or that the driver refused to blow into a screening device. If you've been issued an Immediate Roadside Prohibition, there is bad news and good news.
The Bad News
The bad news is that the Immediate Roadside Prohibition law was drafted to make it difficult (but not quite impossible - see below) for drivers to dispute.