Third-cause fallacy

A variation on the post hoc ergo propter hoc fallacy, third cause fallacy asserts that X causes Y when in reality, X and Y are both caused by Z. When third causes are ignored, it becomes possible to corral shocking statistical evidence in support of a nonexistent causality.

For example: "It seems that every time empty beer cans are piled up in a car, an accident occurs. It seems that the excess weight and shape of the cans must cause other cars to want to crash into the victim car." The fallacy is that the fact that alcohol impairs reaction and judgement is ignored, and instead, the cans are blamed for causing accidents.