Craig Miller/KQED
The population living and working in San Francisco has been increasing in recent years; so has the number of cars trying to get in and out of downtown. The laws of physics are at work here, of course, as more and more people -- and vehicles -- try to squeeze into the 49-square-mile tip of the peninsula bounded by ocean and bay.
One idea that has been floated to deal with this issue is congestion pricing, which has been tried in other cities with mixed results. We put this idea up for discussion, and it generated plenty of controversy.
http://storify.com/kqednews/should-san-francisco-charge-drivers-to-enter-downt-2