Critics who have been saying the government of Scotland inflated its claims of speed camera effectiveness were vindicated Tuesday. The UK Statistics Authority, an independent watchdog agency, issued a report confirming that the country's national statistics failed to adhere to commonly accepted standards. The authority tested the statistical methods used by the Scottish speed camera partnerships in compiling a document known as the Key Scottish Speed Camera Programme Statistics report.

"The methods used to produce the statistics are unsophisticated and do not take into account issues such as regression to the mean or sources of measurement error," the Statistics Authority's audit found. "The report does not discuss non-sampling errors or any limitations to how the statistics can be used."

Last month, an independent review commissioned by the Scottish government identified many of the the same faults (view report). The Statistics Authority went a step further by suggesting the accident numbers are being used for propaganda purposes.

"The weaknesses detailed in the preceding paragraphs, together with the inclusion of the SSCP [Scottish Speed Camera Programme] logo on the report, give the impression that the production and presentation of the statistics is not impartial," the audit found.

The audit noted that when the speed camera program was moved out of the Justice Department and into Transport Scotland, the statistician responsible for monitoring the cameras was folded into a group with political goals.

"While this is not unusual, it does require careful management to ensure that there is no opportunity, or perception of opportunity, for the policy team to influence inappropriately the production of the statistics," the audit noted.

The Statistics Authority had reason to suspect improper influences in the material produced by the Scottish government.

"The assessment team considers that the presentation of the objectives of the SSCP in the introductory paragraph might lead some users to perceive the report as being politically driven, rather than impartial," the audit explained.

The audit faulted officials for ignoring criticism and failing to account for differing views in the final work product.

"The Scottish Government has received correspondence from some anti-speed camera campaigners detailing their concerns with the statistics," the audit noted. "The Scottish Government has replied to this correspondence but it does not seem to have taken the opportunity to engage actively with this community to consider and address their concerns strategically. Neither does there appear to have been any formal engagement or consultation with the wider user (or potential) community. As a result the team has little understanding of how users outside the Scottish Government and the Safety Camera Partnerships use the statistics, and how the statistics could be improved to meet their needs."

Retired engineer Idris Francis was among those who filed a complaint with the Scottish government over the biased statistics. He called the new Statistics Authority audit "devastatingly critical" despite its "polite and reasonable tone."

A copy of the Statistics Authority audit is available in a 140k PDF file at the source link below.