If the city council wants people to drive 25 miles per hour or less on their streets, there has never been anything inhibiting them from designing their streets for slower speeds. The city has always been free, on streets it controls, to implement a design where measured speeds would be as low as 15 mph or even 10 mph. What the city is not allowed to do, without an engineering study, is to enforce a speed limit below 30 miles per hour.
