Leiber incorrectly predicted a catastrophic earthquake would hit California in 1982 due to the coincidental alignment of the moon and planets. Once many people believe something and enjoy a significant amount of communal reinforcement , they get very selective about the type of data they pay attention to in the future. If one believes that during a full moon there is an increase in accidents, one will notice when accidents occur during a full moon, but be inattentive to the moon when accidents occur at other times. If something strange happens and there is a full moon at the time, a causal connection will be assumed. If something strange happens and there is no full moon, no connection is made, but the event is not seen as counterevidence to the belief in full moon causality.
Memories get selective, and perhaps even distorted, to favor a full moon hypothesis.
A tendency to do this over time strengthens one's belief in the relationship between the full moon and a host of unrelated effects. Martin, Kelly and Saklofske reviewed numerous studies done over nearly three decades and found no significant association between phases of the moon and suicide deaths, attempted suicides, or suicide threats. This very unclear statement has to be interpreted. I took it to mean that an average of 175 drunk drivers were caught each day on days one and two of the five-day cycle. Thus, if the average for the whole five-day cycle was only 161, there were substantially fewer drunk drivers caught on the night of the full moon.