Conflicts involving Critical Mass

There have been many conflicts during Critical Mass events since the founding of the worldwide bicycling advocacy event in 1992. The conflicts have resulted in injuries, property damage, and arrests, and both bicyclists and motorized vehicle drivers have been victims. Critics say that Critical Mass, held primarily in large metropolitan cities, is a deliberate attempt to obstruct automotive traffic and disrupt normal city functions, when individuals taking part refuse to obey traffic laws, while participants variously consider it a celebration of cycling, of cyclists' rights, and a practical re-imagining of urban space.

On May 11, 2007, an incident occurred in Berkeley, California, when an elderly motorist stopped at an intersection with dozens of bicycles crossing.Activists claim that the driver shouted, while bicyclists were in the intersection, "I'm sick of you people!" Police have not determined who had the right-of-way. The driver attempted to drive through the intersection. The motorist and his wife, two witnesses, and the police all claimed that the cyclists threw their bicycles under the vehicle. This was disputed by other witnesses. Critical Mass participants then rocked the vehicle, pounded the hood, and broke the windshield while verbally abusing the elderly couple. Approximately $3,000 worth of damage was done to the bicycles. Berkeley police did not make any arrests in the incident.

On May 30, 2003, in Buffalo, New York, during an incident known locally as "Critical Massacre," police stopped two cyclists for "failure to yield to an emergency vehicle." Several people were allegedly attacked by police. Nine cyclists were arrested and three were later convicted, including a journalist.

Chicago Police Department officers are often seen riding with Critical Mass participants, and squad cars block intersections to provide safe passage to Critical Mass cyclists. However, on August 31, 2007, seven riders were arrested on charges of obstructing traffic and disobeying police, and were held overnight. According to some of those arrested, they were released late at night or early in the morning. On multiple occasions, Critical Mass participants attempted to ride on Lake Shore Drive, a road off limits to cyclists. Police prevented participants riding on Lake Shore Drive, by blocking entrance ramps with squad cars when Critical Mass riders approach the road.

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Wikipedia