Is it illegal to refuse a breathalyser?

Under s.6 of the Road Traffic Act 1988, a constable in uniform may require any person driving, attempting to drive, or in charge of a motor vehicle on a road or public place to provide a preliminary breath test. The officer must have reasonable cause to suspect that the person has alcohol in their body or has committed a moving traffic offence.

Refusing to provide a specimen without reasonable excuse is a separate offence under s.6(6) of the Road Traffic Act 1988. A "reasonable excuse" is narrowly interpreted: it means a physical or mental condition that genuinely prevents you from providing the specimen, such as a serious respiratory condition. Nervousness, reluctance, or a desire to speak to a solicitor first do not constitute reasonable excuses.

The distinction between a preliminary breath test (at the roadside) and an evidential breath test (at the police station) matters. The roadside test uses a screening device. If you fail or refuse the roadside test, you will be arrested and taken to a police station for an evidential test under s.7 of the Road Traffic Act 1988. Refusing the evidential test is a more serious offence under s.7(6) and carries a mandatory disqualification.

The penalties for failing to provide a specimen are broadly equivalent to those for drink driving. For a roadside refusal (s.6(6)), the maximum is a level 3 fine (£1,000) and four penalty points. For an evidential refusal at the station (s.7(6)), the maximum is six months' imprisonment, an unlimited fine, and a mandatory disqualification of at least 12 months (or 36 months for a second offence within 10 years).

The Sentencing Council guideline for failing to provide a specimen (s.7(6)) sets a starting point ranging from a fine to 12 weeks' custody depending on the level of impairment and aggravating factors. A community order is typical for a first offence where there was moderate impairment.