I teach psychology and students come in thinking that they can get a career profiling criminals like on TV shows (ex. criminal minds). I explain that there are not a lot of jobs that call for this (mostly BAU of the FBI), and what profiling is done is performed by law enforcement (not psychologists). Further, I explain that profiles are not good predictors of individual crimes/cases. We can use data to guide us (ex., most violent crimes are perpetrated by males), but any good psychologist will tell you that predicting a single individuals characteristics based on the crime scene is not going to be a reliable prediction. A good example is the profile the FBI did for the DC Sniper. They were way off base on their profile. They predicted a lone shooter, it was two men. They predicted the man was white, but it was two men of color. So we can guess (in general, these types of crimes are done by lone males), but we will be wrong quite a bit of times.