43A   Average speed of heavy vehicle is evidence of actual speed in certain circumstances

(1) When section may be relied on
A person who brings proceedings for a speeding offence involving a heavy vehicle may, in accordance with this section, rely on evidence of the average speed of the vehicle between detection points as evidence of the actual speed of the vehicle in order to establish the offence.

(2) Evidence and other matters that may be relied on
The following provisions apply in relation to proceedings for a speeding offence involving a heavy vehicle in which the person bringing the proceedings seeks to rely on evidence of the average speed of the vehicle:

(a)  the average speed of the heavy vehicle calculated in accordance with this section is admissible and is prima facie evidence of the actual speed at which a driver of the vehicle drove the vehicle on a road between the detection points, and

(b)  if there was more than one driver of the heavy vehicle between the detection points—each driver is taken to have driven the heavy vehicle at the average speed of the vehicle calculated in accordance with this section, except as provided by subsection (3), and

(c)  if more than one speed limit applied to a driver of the heavy vehicle between the detection points and the speeding offence is not a speed limiter offence:

(i)  the average speed limit for the driver on a road between the points calculated in accordance with this section is taken (subject to subsection (8)) to be the speed limit that applied to the driver at all times on the road between those points, and

(ii)  a driver of (and any responsible person for) the vehicle may be dealt with under the road transport legislation accordingly, and

(d)  the heavy vehicle and any of its drivers are, for the purposes of calculating the vehicle’s average speed and any average speed limit, taken to have travelled between the detection points by means of the shortest practicable distance between those points regardless of the actual route taken by any of the drivers between the points.

(3)  Subsection (2) (b) does not apply in relation to any driver of a heavy vehicle if the driver establishes any ground of exculpation prescribed by the regulations. The regulations may also provide for the kinds of evidence that may be used in connection with establishing any such ground of exculpation (for example, the provision of a statutory declaration).

(4) How average speed is to be calculated
The average speed of a heavy vehicle between detection points is to be calculated in accordance with the following formula (and expressed in kilometres per hour rounded down to the next whole number):

where:

D_T is the total shortest practicable distance (expressed in kilometres and rounded down to 2 decimal places) that could have been travelled by the vehicle on a road between the detection points.

T is the journey time (expressed in seconds) of the vehicle between the detection points.

(5) How average speed limit is to be calculated
The average speed limit for a driver of a heavy vehicle on a road between detection points in circumstances where more than one speed limit applied to the driver between those points is to be calculated in accordance with the following formula (and expressed in kilometres per hour rounded up to the next whole number):

where:

D_T is the total shortest practicable distance (expressed in kilometres and rounded down to 2 decimal places) that could be travelled by the vehicle on a road between the detection points.

S₁, S₂…S_n are each of the speed limits (expressed in kilometres per hour) that would have applied to a driver of the vehicle if the vehicle were travelling along the shortest practicable distance D_T on a road between the detection points.

D₁, D₂…D_n are each part of the total shortest practicable distance D_T between the detection points (expressed in kilometres and rounded down to 2 decimal places) for the different speed limits S₁, S₂…S_n that would have applied to a driver of the vehicle between the detection points.

(6) Certificate evidence concerning average speed calculations
Any certificates purportedly signed by an approved person for the matters concerned that certify any one or more of the following matters may be tendered in proceedings for a speeding offence involving a heavy vehicle in which the person bringing the proceedings seeks to rely on the vehicle’s average speed and are admissible in the proceedings and are prima facie evidence of any of the matters that are certified:

(a)  the shortest practicable distance, expressed in kilometres and rounded down to 2 decimal places, that could be travelled by a vehicle on a road between the detection points,

(b)  if more than one speed limit applied to a driver of a vehicle between the detection points (measured along that shortest practicable distance):

(i)  each distance for which each speed limit applied to the driver, expressed in kilometres and rounded down to 2 decimal places, and

(ii)  the average speed limit calculated in accordance with this section that applied to the driver between the points (including an average speed limit calculated in accordance with this section using computer programs or electronic equipment),

(c)  the average speed calculated in accordance with this section at which a vehicle travelled between the points (including an average speed calculated in accordance with this section using computer programs or electronic equipment).

(7) Section does not exclude other modes of proof of speeding offences
This section is in addition to, and does not derogate from, any other mode of proof of the speed of a heavy vehicle.

(8)  Without limiting subsection (7), a court in proceedings for a speeding offence in which the person bringing the proceedings is seeking to rely on evidence of the average speed of the vehicle may convict a person of the offence relying on evidence of the actual speed of the vehicle at a particular point of its journey between detection points (instead of evidence of an average speed or average speed limit) if the court is satisfied that:

(a)  evidence in the proceedings (other than evidence establishing the average speed) establishes the actual speed at which the driver was driving, and the actual speed limit that applied to the driver, at that point, and

(b)  the use of the actual speed and actual speed limit rather than the average speed (and, where relevant, the average speed limit) demonstrates that the driver exceeded the speed limit by a greater speed than that indicated by the use of the average speed or average speed limit.

Note. Assume, for example, that the average speed of a heavy vehicle calculated in accordance with this section between detection points is 120 kilometres per hour along a length of road for which the speed limit is 90 kilometres per hour. The use of the average speed of the vehicle indicates that the speed limit was exceeded by 30 kilometres per hour.

Assume, as well, that a police officer also measured the speed of the vehicle at some point during the same journey at 130 kilometres per hour using an approved speed measuring device. Using the police officer’s measurement, the driver was exceeding the speed limit by 40 kilometres per hour at that point.

A court in proceedings to which this section applies may rely on evidence obtained by the police officer rather than the average speed to convict a person of the speeding offence.

(9) Reliance on average speed does not affect validity of driver licence suspension notices
For the avoidance of doubt, the validity of a suspension notice given to a person under section 205 or 206 of the Road Transport (General) Act 2005 for a speeding offence may not be challenged or called into question in any proceedings only because the average speed that is relied on in proceedings or a penalty notice for the offence is less than a speed for which a notice may be issued under section 205 or 206.

(10) Definitions
In this section:

approved person means:

(a)  in relation to certifying distances for the purposes of this section—a registered land surveyor within the meaning of the Surveying and Spatial Information Act 2002, and

(b)  in relation to certifying any other matter for the purposes of this section—a person (or a person belonging to a class of persons) authorised by the Authority to issue certificates for the purposes of this section.

detection points means the different points on a road by reference to which the average speed of a heavy vehicle is proposed to be calculated for the purposes of this section.

heavy vehicle has the same meaning as in the Road Transport (General) Act 2005.

journey time, in relation to a heavy vehicle between detection points, means the total time that elapsed between the heavy vehicle passing the first and last detection points.

road transport legislation has the same meaning as in the Road Transport (General) Act 2005.

shortest practicable distance between detection points on a road means the shortest distance between those points that a driver of a heavy vehicle could have used to travel between the points without contravening any road rules applicable to the driver under this Act.

speed limiter offence means a speed limiter offence within the meaning of Division 2A of Part 5.

speeding offence means:

(a)  an offence against this Act or the regulations of failing to obey a speed limit, or

(b)  a speed limiter offence.