Legally accurate. This means that the measurement is accepted as scientific evidence by the standards as prescribed by scientific bodies. This "should" be the only evidence accepted by the courts, but has been ignored and tended to be ignored by the police force, and the courts because of lack of technical knowledge and deceit by corporations all over the world. Dont forget, where their equipment is being used, they usually (not always) get a cut. They also "test" their own equipment in cases and it may be that due to lessening income due to drivers complying after being stung by huge fines they "fix" them to read higher than the actual speed. They wouldnt do that? I know of a lot of fraud involving corporations. You only have to read the Newspapers. See this >> From Federal MP Dennis Jensens maiden speech in Western Australia.
On the subject of raising revenue, state governments have become so greedy that they blithely ignore simple fairness in enforcing speed limits that are quite often not set on a scientific basis but established from simple guesswork or, worse, with a view to maximising revenue from speed enforcement. Speedometer accuracy is legislated to be within 10 per cent by Australian design regulation 18, yet in many cases this is ignored in the threshold that is used to enforce speed limits. Picture hiring a car at an airport, obeying the speed limit according to the ADR-compliant speedometer but then getting a speeding ticket due to overzealous enforcement. As if this were not bad enough, speed-measuring devices in many states have scientifically unsupportable tolerances applied, blatantly ignoring Australian standards.
In many cases, they are supported by suppliers, such as Multanova, who are either totally technically inept or simply not beyond using lies to support the illegitimate tolerances to ingratiate themselves with the authorities to ensure repeat business. This highlights the need to generate legally enforceable national standards. We do not need police standing adversely affected and undermined by opportunistic traffic enforcement policies. Ensuring fair enforcement thresholds that allow for speedometer errors can be achieved by an amendment to the National Measurement Act. Scientifically justifiable speed-reading device tolerances could be enforced by ensuring that Australia standards have the full backing of legislation. Currently they do not, and the states are thumbing their noses at these standards. Here is his website. I believe he is an honest politician, which is rare.