Bicyclists are legally allowed to ride the streets of Chicago. Also, they must follow traffic laws like other drivers. Yet the small size of a bicycle makes them more difficult to see than other vehicles. This increases the odds that a distracted car driver will strike a bicyclist.
Similarly, many areas of Chicago are designated for pedestrian walking or pedestrian crossing near the shoulders of roads at intersections. If a driver is not paying attention, a collision with a pedestrian may result, potentially with fatal consequences.