In peer pressure, there may be different ways of convincing someone to do something he/she doesn't want to do at first. One of them is reasoning tactic, by which a person trying to make the other change his/her mind uses a logical argument to prove his/her point.
The person who is trying to persuade someone to smoke pot says: "Act like your sister. She smoked pot and never got caught." He is giving a logical argument: Your sister smoked pot. She never got caught. You can smoke pot. You will never got caught. By logic, you can do it because your sister never got caught.
