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Arrest after a preliminary test and entry after an injury accident

ss.6D–6ERoad Traffic Act 1988

Lets a constable arrest without warrant a person whose preliminary breath or drug test indicates they are over the limit, or who fails to co-operate with a preliminary test, and to enter any place to test or arrest after an accident involving injury.

Arrest after a preliminary test and entry after an injury accident · Road Traffic Act 1988, ss.6D–6ECard 43 / 59

When you can use it

s.6D(1)A preliminary breath test or preliminary drug test has been carried out
As a result, the constable reasonably suspects alcohol in breath or blood is over the prescribed limit, or a specified controlled drug in blood or urine is over its specified limit
s.6D(2)Or the person failed to co-operate with a preliminary test required under s.6, and the constable reasonably suspects they have alcohol or a drug in their body or are under the influence of a drug
s.6D(3)The person is not at a hospital as a patient
s.6E(1)Entry only after an accident the constable reasonably suspects involved injury to any person
Entry must be to require a preliminary test under s.6(5), or to arrest under s.6D

What it allows

Arresting the person without warrant on the s.6D grounds.
Instead of taking them to a police station, detaining them at or near the place of the preliminary test (or where it would have been given) to require evidential specimens there under s.7 (s.6D(2A)).
After an injury accident, entering any place, using reasonable force if necessary, to require a preliminary test or to arrest (s.6E).

Key definitions

Preliminary test – s.6(8): a preliminary breath test (s.6A), impairment test (s.6B) or drug test (s.6C).
Prescribed limit – s.11: 35 microgrammes of alcohol in 100 millilitres of breath, 80 milligrammes in 100 millilitres of blood, or 107 milligrammes in 100 millilitres of urine.
Specified controlled drug – a drug, and its limit, specified in regulations under s.5A.
Evidential breath result – s.6D(1A): giving s.7 breath specimens does not stop a s.6D(1) arrest if the constable has reasonable cause to believe the device gave an unreliable reading.

Safeguards

Tell the person they are under arrest and the grounds (PACE s.28), and caution them (Code C, para 10.4).
A hospital patient cannot be arrested under s.6D. Any test or specimen request at hospital needs the doctor in immediate charge to be told first, and is barred if they object that it would harm the patient’s care (s.9).
The s.6E entry power does not extend to Scotland (s.6E(2)).

Good to know

Failing without reasonable excuse to co-operate with a preliminary test is an offence (s.6(6)).
After an accident under s.6(5), the constable does not need to be in uniform. Tests under s.6(2) to (4) need a uniformed constable (s.6(7)).
Exam trap: s.6E applies only where injury is suspected. After a damage-only accident, entry needs consent or another power, such as PACE s.17(1)(c)(iiia) to arrest for the s.4 unfit-to-drive offence.
s.6D is a free-standing arrest power, so the PACE s.24 necessity test does not apply. Code G does not cover it (Code G, Note 1A).

Legislation: Road Traffic Act 1988, ss.6D–6E (opens legislation.gov.uk in a new tab)
Who can use it: A constable
Last checked: 3 November 2026, against the current law on legislation.gov.uk

Arrest after a preliminary test and entry after an injury accident: questions people ask

When can the police use arrest after a preliminary test and entry after an injury accident?

1. A preliminary breath test or preliminary drug test has been carried out 2. As a result, the constable reasonably suspects alcohol in breath or blood is over the prescribed limit, or a specified controlled drug in blood or urine is over its specified limit 3. Or the person failed to co-operate with a preliminary test required under s.6, and the constable reasonably suspects they have alcohol or a drug in their body or are under the influence of a drug 4. The person is not at a hospital as a patient 5. Entry only after an accident the constable reasonably suspects involved injury to any person 6. Entry must be to require a preliminary test under s.6(5), or to arrest under s.6D

Who can use arrest after a preliminary test and entry after an injury accident?

A constable.

What law gives the power for arrest after a preliminary test and entry after an injury accident?

Road Traffic Act 1988, ss.6D–6E.

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