When accidents aren't accidents.

A single driver on a straight road hits a tree at 70 mph and dies. No skid marks. Dry conditions. Officers at the scene list the cause of death as improper driving. But was it?

Police have long theorized that many such otherwise inexplicable crashes are actually disguised suicides. And many researchers believe that suicides disguised as traffic accidents are far more prevalent than previously thought. However, the information necessary to conclude that the driver's intent was to terminate his/her life is generally unavailable and must be proven. Even when suicide is strongly suspected but a suicide note is not found, the case will be classified an "accident."

While there are few studies to substantiate "autocide," sociologist David Phillips of the University of California, San Diego, offered the most solid evidence yet that a number of suicides deliberately drive to their deaths in the family car.

Phillips' study stemmed from a paper he published in 1974 arguing that some suicides were clearly imitative: in the weeks following a prominent suicide, the number of ordinary Americans taking their own lives rises. Phillips later reasoned that if the automobile was a suicide weapon, traffic deaths should increase after widely reported suicides. He analyzed California traffic fatalities from 1966 to 1973, comparing figures for ordinary weeks with statistics for weeks following suicides that were highly publicized in the state, including those of Playwright William Inge, Japanese Novelist Yukio Mishima and California Wine Maker A. Korbel. Phillips' finding: on the third day after such a suicide, auto fatalities rose by 30%; they leveled off for the week at 9% above normal. "In general," notes Phillips, "the more publicity given to the suicide story, the more the number of auto fatalities rises."

One large-scale community survey among suicidal persons provided the following numbers: "Of those who reported planning a suicide, 14.8% had conceived to have a motor vehicle “accident”. Of all attempters, 8.3% had previously attempted via motor vehicle collision.

A second study (Schmidt, Perlin, Towns, Fisher, & Shaffer 1972) led to considerable speculation that a significant albeit unknown proportion of vehicular deaths classified as accidents are in fact suicides. As they argued, the single-car, single-occupant fatal crash is especially suspect and constitute from 1.6% to 5% of all vehicular fatalities.

Except for the Depression year of 1932, the current suicide rate in the U.S. is the highest in history.