Katz looked at a wide variety of sources, including biographies and autobiographies of criminals, journalistic accounts, and participant observation studies, and tried to read into these accounts the real explanation that the criminals had for the criminal behavior. He then applied this technique to five types of crimes: passion murders, adolescent property crime, gang violence, persistent robbery, and coldblooded murder. In each case, he found that the criminal is engaged in a "project”--that is, is trying to accomplish something by committing the crime. That project is primarily moral--that is, it involves right and wrong, justice and injustice. It therefore involves emotions that have strong moral components: humiliation, righteousness, arrogance, ridicule, cynicism, defilement, and vengeance. In each case, the criminal action itself is fundamentally an attempt to transcend a moral challenge faced by the criminal in the immediate situation.