To all the self-righteous commenters who come out of the woodwork every time I suggest that some neighborhood streets might be safer if speed limits were reduced to 20 mph, rather than 30 or 40 (chance of being killed if you're hit at 20mph: 5 percent; chance of being killed at 30 mph: 45 percent): Be glad you don't live in Washington, D.C., where they're talking about lowering speed limits (on residential streets! not freeways!) to as low as 15 mph. 

Greater Greater Washington reports :

[D.C. council member] Muriel Bowser wants to lower residential speed limits from 25 to 15 mph. Slower speeds reduce the number and severity of injuries to pedestrians hit by drivers.

A separate proposal would mandate that if one car is stopped at a pedestrian crossing, any cars coming up behind it should also have to stop, rather than coming around and passing them, a major factor in many pedestrian deaths, DCist reports. The majority of pedestrian-car collisions in Seattle occur when the driver fails to yield the right-of-way to a pedestrian.

P.S. It's not just me and the hippies on the D.C. council. Council member Sally Bagshaw wrote a blog post late last month supporting the statewide speed limit proposal, which would allow cities to lower speed limits on some residential streets without going through costly engineering studies.