In Lumsden v Police [2019] SASC 178 Stanley J upheld an appeal by a police officer who had been convicted of aggravated driving without due care contrary to s 45(1) of the Road Traffic Act 1961 (SA).

The defendant officer had been engaged in a traffic stop.  He got out of his police car without first applying the hand brake and putting it into ‘park’. As he got out the car rolled forward. Even though he was part way out of the car, he attempted to stop it by putting his foot on the brake. He accidentally put his foot on the accelerator and the car ran over the motorcyclist, and motorcycle, that he had stopped.  The motorcyclist suffered serious injuries.

The defendant police officer argued that the magistrate failed to consider the defence provided by s 65 of the Police Act 1988 (SA).  That section says (emphasis added)

A member of SA Police does not incur any civil or criminal liability for an honest act or omission in the exercise or discharge, or the purported exercise or discharge, of a power, function or duty conferred or imposed by or under this Act or any other Act or law.

That section is unusual. Most sections like this refer to civil, not criminal liability – see for example Rural Fires Act 1987 (NSW) s 128 discussed in the various decisions of R v Wells (see RFS fatal collision and s 128 of the Rural Fires Act (October 14, 2016) and the decision in Workcover v NSW Fire Brigades [2006] NSWIRComm 356 which found that s 78 of the Fire Brigades Act 1989 (NSW) (as it then was) did not extend to provide immunity from criminal prosecution).

The South Australian provision explicitly does extend to criminal liability (see also Fire and Emergency Services Act 2005 (SA) s 127).  Justice Stanley, hearing the appeal from the Magistrate, found that the magistrate made an error in not applying s 65.

His Honour said (at [37]-[39):

I am satisfied that the appellant was performing a traffic stop. I am further satisfied that at the time when the appellant attempted to alight from the vehicle without engaging the transmission into the “park” position he was purporting to exercise or discharge a function conferred or imposed under the Police Act. In addition, in doing so the appellant was in the process of exercising or purporting to exercise common law duties of a police officer to investigate a possible crime and to control traffic. At the very least the respondent has not excluded that as a reasonable possibility.

The magistrate found that the appellant attempted to alight from the police vehicle mistakenly believing that he had placed the transmission into park and that he considered it safe to get out of the vehicle.  By implication, that is a finding that the appellant’s relevant act and omission was honest.  In any event, the respondent carried the onus of disproving this fact and has not excluded that as a reasonable possibility.

On that basis the immunity conferred by s 65(1) applied.  Accordingly, the magistrate should have returned a verdict of not guilty.  It follows that the conviction must be set aside and a verdict of not guilty substituted.

His Honour also considered a defence raised by s 45 of the Road Traffic Act 1961 (SA).  That section says

(1)        A person must not drive a vehicle without due care or attention or without reasonable consideration for other persons using the road…

(4a)      It is a defence to a charge of an offence against this section for the defendant to prove that the defendant was, at the time of the offence—

(a) carrying out duties as an emergency worker; and

(b) acting in accordance with the directions of the defendant’s employing authority; and

(c) acting reasonably in the circumstances as the defendant believed them to be.

An emergency worker is ‘a police officer or a person who is an emergency worker as defined by the regulations for the purposes of this section’.  The Road Traffic (Miscellaneous) Regulations 2014 (SA) r 61 extend the definition to include ‘members of an emergency services organisation within the meaning of the Fire and Emergency Services Act 2005’ and ‘persons engaged in the provision of emergency ambulance services under section 57(1) of the Health Care Act 2008 on behalf of SA Ambulance Service Inc’.

The circumstances, as the defendant believed them to be, was that the car was in park with the handbrake on.  At [53]-[54] His Honour said:

I am satisfied that the third limb of the defence was made out.  The third limb of the defence has an objective and a subjective test.  For the purposes of placitum (c) the trier of fact must be satisfied that the emergency worker was acting reasonably in the prescribed circumstances.  That is the objective test.  The prescribed circumstances are the circumstances as the defendant believed them to be.  That is the subjective test.

In this case the appellant believed the circumstances to be that he had placed the transmission into park.  In those circumstances it was objectively reasonable for him to alight from the vehicle.  In those circumstances it was objectively safe to do so.

There is a common law defence of mistake that says an accused is not guilty of a crime if he or she has an honest and reasonable belief in facts which, if true, would make the act innocent (called the Proudman v Dayman defence after the decision in Proudman v Dayman [1941] HCA 28)).  For that common law defence to apply the defendant police officer would have to have believed that the vehicle was in park and that belief would have to have been based on reasonable grounds.  In this case the defendant would not have succeeded based on the common law.  His Honour said (at [48]):

…  the evidentiary onus was discharged by the appellant when he gave evidence that he believed he had placed the transmission in park and considered it was safe to get out of the police vehicle.  As I have noted, the magistrate accepted this evidence.  It follows that the subjective element of the defence was not disproved.  However, the magistrate rejected the defence on the basis that the objective element was disproved.  The magistrate found the prosecution had proved that the appellant’s belief was not reasonable.  The magistrate found that leaving the engine on and the gear shift in drive was not a reasonable mistake of fact.

The paradox is that the common law requires the belief in facts (in this case that the car was in park and the brake applied) be both honest and reasonable in the circumstances.  The statutory defence in s 45 for emergency workers only requires that the belief be honestly held and that the actions of the emergency worker be a reasonable action in light of that belief.  The belief itself need not be ‘reasonably’ held.   His Honour noted the paradox and said:

I referred earlier to the paradox of the appellant succeeding on the defence created by s 45(4a) but failing on the defence of honest and reasonable mistake of fact. The appellant succeeds on the emergency worker defence where he failed on the Proudman v Dayman defence because the tests under each differ.  For the purposes of the Proudman v Dayman defence the issue is whether the appellant’s mistake of fact is objectively reasonable, while for the purposes of s 45(4a) the issue is whether the appellant’s acts are reasonable given the circumstances as he subjectively believed them to be. The Proudman v Dayman defence failed because the prosecution disproved the reasonableness of the appellant’s mistake in believing that the vehicle had been placed in park. On the other hand, the appellant made out the s 45(4a) defence because he proved that, at the time of the act and omission which constituted the offence of driving without due care, his act and omission was reasonable in the circumstances as he believed them to be.

There is a lower standard of behaviour expected of SA police and emergency workers than other road users.


The result here is surprising and I would suggest unique to SA given the terms of the Police Act and the Road Traffic Act (and the Fire and Emergency Services Act).  Explicitly extending protection to criminal liability is unusual and I am not aware of a defence such as the Road Traffic Act s 4(4a) in other jurisdictions.   It is an exemption that goes much further than that seen in rule 306 of the Australian Road Rules and discussed in other posts in this blog.

As a result, Police Officer Lumsden stands acquitted of the criminal charges.  He is also not civilly liable for any injuries caused to the motorcyclist however the Police Act 1998 (SA) s 65(2) does provide that the state of South Australia will carry any liability to pay compensation to the injured person.  The injured person is not denied his civil remedy to meet the costs of his injuries and losses, but Officer Lumsden is not guilty of any crime.