Laws Around Unconcious Pathology Collection

Theoretical situation more out of interest than anything

Adult patient in ED, unconscious, and let’s say is stable. I know its policy for us to take a BAL if the
presentation is related to a car accident and a few other scenarios. But for argument’s sake - say it is not a car accident or is unclear of the mechanism for this situation.

A police officer attends ED and requests that a urine/blood drug, alcohol sample is collected. Legally
are we obligated to collect those tests, do we have the right to refuse collection or should we be refusing collection regardless? Does this breach laws around 'harming' a patient or performing unnecessary procedures not necessary for patient immediate care and safety?

I am ignoring the argument here that we need to search for drugs taken to ensure they have not OD'd on something or intentional harm of course - solely focusing on testing for a prosecution approach

I appreciate they are time sensitive collections for the test, but at same point can be incriminating
the patient and is not 'life-or-limb' and thus should also not be enforcing procedures that are not necessary for his survival. The same technically goes for doing a BAL after a car accident if they unconscious and no NOK to consent IMO.

Thoughts on this, has anyone come across this or knows the laws around this.

-legality of collecting these not 'necessary' tests for patient care while they are unconscious

-Without a court order can we be collecting them or enforced to collect them by the police force or
any administrative body?

Keen to see what people think or if people know of the actual laws/rules around this.