Transportation

By their very nature, city streets are filled with a broad spectrum of users, from children walking with their parents all the way up to tractor-trailer trucks, which can weigh 80,000 pounds or more. With such an immense disparity in size, those outside motorized vehicles are the ones most likely to suffer in a crash — in 2008, more than 5,000 pedestrians and cyclists were killed by vehicles in the United States, and more than 120,000 were injured.

Shocking videos of a man being bloodied and dragged screaming off an overbooked United Express flight have inspired some people to query their rights when flying America’s increasingly crowded skies.