Defensive Attribution is a mental mechanism used to avoid the worry associated with the belief that one will be a victim or cause of something negative. This commonly occurs when encountering a person who has experienced a mishap, such as a car accident or being attacked. A person will place more responsibility on a victim or a harm doer depending on the severity of the incident and how similar the victim and observer are. The more serious a situation is, the more responsibility is placed on the victim or the harm doer as a way of reducing emotional distress and worry of thinking that it could happen to you. In essence, this helps the person feel less worried that the same bad thing will happen to them.
One example is when a woman blames another women who was raped. A person may place responsibility on the victim in order to reduce the worry that the same situation could happen to them. By placing responsibility on the victim it mentally reassures a person that the situation couldn't happen to them (e.g., "They were asking for trouble because they were dressed inappropriately and walking at night. That would never happen to me because I wouldn't do that"). Another type of defensive attribution is optimism bias, which is when a person believes that positive things happen to them more frequently than other people and negative things happen less frequently. An example of this is an obese person who thinks they are different from others and won't have problems with diabetes or heart disease like other people.