Reader Tom Eisenman shared with me an article in the September issue of New Urban News, laying out an argument that tall, vertical objects along streets, like trees and buildings, are deterrents for car crashes—in contrast to the frequent input of "transportation engineers, who contend that a wide travel corridor, free of obstacles, is needed to protect the lives of errant motorists." More from the article:

Though engineers generally assert that wide clear areas safeguard motorists who run off the roads, [Texas A&M assistant professor of transportation Eric] Dumbaugh looked at accident records and found that, on the contrary, wide-open corridors encourage motorists to speed, bringing on more crashes. By contrast, tree-lined roadways cause motorists to slow down and drive more carefully, Dumbaugh says.

Dumbaugh examined crash statistics and found that tree-lined streets experience fewer accidents than do “forgiving roadsides”—those that have been kept free of large, inflexible objects. He points to “a growing body of evidence suggesting that the inclusion of trees and other streetscape features in the roadside environment may actually reduce crashes and injuries on urban roadways.”

While people playing basketball in the street is technically illegal in Springfield, I wonder if it could be considered one of our "streetscape features." Such games do effectively slow down traffic. Same for people parked far away from the curb, hazards flashing, no one at the wheel, while the driver runs into a convenience store. Life in the dense inner city: it’s safer for driving!

Dumbaugh’s 2005 article, "Safe Streets, Livable Streets" (PDF), published in the Journal of the American Planning Association, is worth a close read. For more similar stuff, check out Dom Nozzi’s walkablestreets.com, which features a wide selection of article links on this subject.