There are two ways of using sec checks data: 1) To embarrass a person; 2) To report crimes to the officials.
The embarrassing data includes the abnormal sex behavior such as sex with a dominatrix, homosexuality, group sex, necrophilia (this is a sign of a severe mental disorder), bestiality, etc. Except for bestiality, which is a form of animal abuse, these sexual deviations do not constitute a crime. But it is understandable why majority of the people with these experiences prefer not to discuss their indiscretions.
Some people have committed financial crimes such as embezzlement, buying of stolen property, financial fraud, etc. These individuals are vulnerable to CoS blackmail.
My encounter with Scientology was brief, I haven't have heard about CoS using the sec check data against its real or perceived enemies.
Did CoS use sec check data against you or someone you know?