Investigative psychology is the bottom-up approach to profiling developed by David Canter, who proposed that profiling can and should be based in psychological theory and research. Key assumptions made by this approach include: interpersonal coherence (there is a consistency between the way offenders interact with their victims and with others in their everyday lives); time and place (the time and location of an offender’s crime will communicate something about their own place of residence/employment); and criminal characteristics (characteristics about the offender can help to classify them, which helps the police investigation).