I read Mr. Smyth’s opinion piece supporting speed cams on freeways.
Just in case you are also a supporter of red-light cameras, I want to bring the following to your attention.
Staff at the City of San Francisco MTA – which operates the city’s large red-light camera program – recently published a report in which they looked at the effect the 19-year-old program has had upon the incidents of broadside crashes with injury.
While their report leads off with an impressive graph showing a dramatic decrease in crashes citywide, the intersection-by-intersection charts for just the intersections having red-light cameras tell a very different story: At the vast majority of those intersections, the red-light camera(s) clearly had no beneficial effect.
Instead, the occasions when crashes dropped were associated with changes like making the yellows longer, adding an all-red interval (both of which are cheap to do), the addition of an arrow for left turns, or a general upgrade to the signal.