[1][2] One of the first American profilers was FBI agent John E. Douglas, who was also instrumental in developing the behavioral science method of law enforcement.
The FBI classification system is derived from a single interview-based research study with a small sample of apprehended serial killers who operated in North America.
Further limitations of the original study include the subject selection process that relied on non-random self-selection, and the extensive use of potentially biased data.
[15] David Canter examined the relationship between the behavioral styles and background characteristics of 100 serial-homicide offenders using a multidimensional scaling (MDS) procedure called smallest-space analysis (SSA) that statistically represents the co-occurrence of variables.
No evidence was found to support the co-occurrence of behavioral styles or background characteristics related to the organized/disorganized taxonomy as proposed in the Crime Classification Manual (CCM).