Just before sunrise on March 5, 2010, a tour bus carrying 22 passengers from Mexico to California (CA) ran off an Arizona (AZ) highway, rolled and killed six riders. Another 16 passengers suffered injuries requiring hospital care.

Making the tragic situation worse, newspapers such as the Arizona Republic are reporting that the California company that operated the bus, Tierra Santa Inc., “has a history of safety violations, no federal record of insurance and could not legally carry passengers in Arizona.” This inexcusable situation is unfortunately common.

As I noted last summer, an analysis of data from the Federal Motor Carrier Safety Administration, which regulates interstate buses, showed that nearly two dozen companies ordered to cease operations after committing serious safety violations continued to put their vehicles on the road. Bus safety has received increasing attention as the number of incidents such as this week’s elementary school bus accident in Portsmouth, last fall’s accident involving a bus bringing the King’s Fork field hockey team back from a game and the 2008 fatal bus crash near Houston in which, again, passengers traveling from Mexico died by the side of a highway.

When children or adults board a bus, they literally entrust their lives and health to the driver and the bus company, school district or transit agency that operates the bus. Tierra Santa Inc. appears to have violated this trust with passengers aboard its bus Friday morning by running an unsafe bus and operating in defiance of applicable laws. My thoughts go out to those who lost their lives and became hospitalized, as well as to the victims’ families.