The Trailside Killer of San Francisco
In 1980, Douglas writes, the police from the San Francisco Bay area had requested the FBI's help on the series of hiking path murders. By this time, the press had already dubbed the offender the "Trailside Killer." The initial request went to Special Agent Roy Hazelwood, who was a sex crimes expert. He and Douglas had published an article that year about lust murder, setting forth the distinctions between organized and disorganized killers, and Hazelwood believed that sexual assault was generally motivated by aggression, sex or power. The fantasies that occur around puberty influenced the type of victim a lust killer selects, as well as his approach, preferred sexual activities, rituals, and decision to complete the act (or not) with murder.
Hazelwood viewed sex offenders as either impulsive or ritualistic. Impulsive offenders were opportunistic and generally of lower intelligence and economic means, and their sexual behavior often served power or anger needs. Ritualistic offenders, on the other hand, indulged in paraphilias and compulsive behaviors that satisfied a specific psychological need. As they centered their lives around this activity, they learned to lie and manipulate in order to keep it hidden from others and secretly active.
Hazelwood discussed the case with Douglas, who at that time was the Bureau's only full-time profiler in the field, and they worked it together. They were both part of the first generation of FBI profilers, an elite group of agents hand-picked to learn the art of the psychological analysis of crime scenes. They had yet to have any striking cases that would gain them national exposure, but they were being consulted more often by local jurisdictions whose investigators were willing to look into any avenue for assistance.
The basic idea of a criminal profile was to acquire a body of information that revealed a common pattern for a general description of an UNSUB (unknown subject) in terms of habit, possible employment, martial status, mental state, and personality traits. Probing for an experiential assessment of a criminal from a series of crime scenes involved a detailed victimology — learning significant facts about the victim's life, especially in the days and hours leading up to his or her death. Their movements were mapped and investigators study all of their personal communications for signals to where they may have crossed paths with a viable suspect.
Douglas went to San Francisco to examine the crime scene data and case photos, and he said the killer would be familiar with the area (so a local man), but he was shy, reclusive, and may have a speech impediment. Contrary to what some local psychologists had decided, who had described the offender as charming, sophisticated and good-looking, Douglas thought he would be unsure of himself in social situations. He chose victims of opportunity rather than preferring a certain victim type. He was white, intelligent, blue collar, and had spent time in jail. His MO was to approach from behind, if possible, and become aggressive to overwhelm the victim. He was "like a spider waiting for a bug to fly into his web." He'd have a history of at least two of the three background indicators: fire-starting, bed-wetting, and cruelty animals. Douglas although thought he was probably in his thirties and had recently experienced some precipitating stressors. While he had committed rape before this series of murders, he had not killed.
That Douglas had been so specific about the speech impediment drew a lot of doubt from the task force members; they wondered how he could know something like that. Douglas explained that the secluded killing areas, the method of approach, and the fact that the offender did not approach his victims in a social situation to lure them indicated some degree of shyness or shame. He believed it was due to a physical malady. Overpowering someone gave the killer some sense of compensation for his handicap. "He has some kind of defect that really bothers him," he said.
The profile did not offer anything that one could call a viable lead unless they had a suspect, so the police were still in the same place. They had a guy who roamed the thickest areas of the hiking trails, lying in wait for potential victims. With the many miles of trails around San Francisco, there wasn't much they could do.
After Douglas returned to Quantico, the killer struck again in March 1981. This time, though, he made a serious blunder. For him, it was the beginning of the end, even though he had switched to yet another park.