Mr Agar was accused of speeding, with his alleged speed detected by a Gatsometer MRC System speed camera. (The offence occurred before the current Road Safety (General) Regulations 2009 and Road Safety Road Rules 2009 commenced operation. But despite different regulation numbers, the provisions remain largely the same in their operation.) It seems Mr Agar has a keen interest in speed cameras: according to the Herald-Sun, he operates the Fight Fines website. (Who-is also shows the domain owner as Carl Agar.)
Mr Agar's argument centred largely on the operation of Road Safety (General) Regulations 1999 reg 306, which relevantly provided that a prescribed speed measuring device had to be tested in a prescribed manner:
306 Testing of speed measuring devices
For the purposes of sections 79, 81 and 84(7) of the Act, a speed measuring device is tested in the prescribed manner if the testing officer who tests the device—
(a) is satisfied that the device is in a satisfactory electrical condition and, in particular, that any maintenance carried out on the device has been carried out in a satisfactory manner; and
(b) is satisfied that the device is properly calibrated so that it operates within the following limits of error—
...(c) records and retains the results of the test, including—
(ii) in the case of an automatic detection device referred to in regulation 302(b) and (c), the frequencies or speeds at which calibration is effected indicate speed readings within a limit of error not greater than or less than 3 kilometres per hour or 3 percent (whichever is greater) of the true speeds determinable from those frequencies or speeds;
(i) a statement showing the frequencies or speeds at which the calibration was effected and the number of times that each frequency or speed the calibration was effected; and
(ii) the date of the test and the ambient temperature at the time of the test.
Mr Agar focussed on the meaning of ‘satisfied’, and argued the testing officer could not or ought not be ‘satisfied’ the device was tested as required.
 Mr Agar advanced similar arguments of construction before me. Those arguments were presented both in detailed written form, and also in oral submissions. I was much assisted by Mr Agar’s oral argument in understanding the essence of his complaints. His arguments may be summarised as follows:
(a) “satisfied” cannot be judged purely by the subjective state of mind on the part of the testing officer — it must at least be subject to some criteria of reasonableness;
(b) “satisfied”, in respect of testing a measuring device’s condition and accuracy, must mean satisfied against some sort of standard: and that standard must at least require that the test be verifiable, reproducible and have accommodated all possible variables that might affect the device’s operation (which, for example, would require testing in the field as well as the laboratory);
(c) the word “satisfied” must be understood to mean “satisfied in accordance with accepted metrological principles” because, since 1959, Australia has been a signatory to the Convention that established the International Organisation of Legal Metrology, and legislation should be construed in accordance with our treaty obligations; and
(d) further, because a “testing officer” as defined in reg 105 includes, amongst the three classes of persons so defined, one class which, by definition, would apply metrological principles, that means that all testing officers are required to do so when carrying out a task under the regulations.
The Court concluded as a matter of statutory construction the Regulations didn't import standards from the International Organisation of Legal Meteorology, or the National Measurement Act 1960 (Cth) or National Measurement Regulations 1999 (Cth).
The Court also rejected an argument that a court must take into account the speedometer tolarance permitted under the Australian Design Rules incorporated in the Road Safety (Vehicle) Regulations 1999, and affirmed that a defence of honest and reasonable mistake of fact isn't available upon a charge of speeding, citing Kearon v Grant  1 VR 321.
The application for the writ quashing the County Court's decision was refused.