Ernst Geiger contacted an FBI office in Vienna
and, through them, he explained what he needed to Gregg McCrary in the Behavioral Science Unit (BSU) at Quantico, Virginia
. McCrary details their meeting and his involvement in the rest of the case in The Unknown Darkness
. Geiger enlisted Thomas Mueller, Chief of the Criminal Psychology Service in the Federal Ministry of the Interior, to go with him to the States, and for two weeks, they learned how the BSU worked on such cases. Profiling was not involved, since these cases were well beyond that stage, but the area of Criminal Investigative Analysis that was relevant was case linkageshowing that the behaviors were consistent across the cases such that it was clear that the same perpetrator committed them all.
Initially, McCrary worked only on the crime and crime scene details, without access to information about the suspect. That involved putting them all in order to see evidence of change or escalation, and also filling out detailed forms for each murder to enter them into the database for the Violent Crime Apprehension Program (VICAP). McCrary knew that if this killer was responsible for all eleven murders, he was rare, because while killers may cross a border, to travel internationally in the way this case showed, did not happen often. A defense attorney could easily find an expert to say so. Nevertheless, McCrary spotted a pattern.
We had a similar victimology and manner of disposal, he writes. Most of these women had been prostitutes and were left outside, with branches or foliage placed over them. We had no semen left on or in [most of] those bodies. The cause of death for those on which we could tell was strangulation, but some bodies were too decomposed to make a determination. Most had restraint bruises on their arms and wrists. No one had seen them getting into a car, so this offender had been careful. There was an absence of any indication of sexual assault. The trace evidence was next to none as well, and he appeared to have a calculated MO. He was smart and he was organized.
The VICAP database contained ten to twelve thousand solved and unsolved homicide cases at that time. They used fifteen cross-referenced criteria for the search, and they ended up matching the eleven with one another but with only one other in California, and in that one the killer had already been convicted. In other words, McCrary interprets, it would be highly unusual to have more than one guy engaging in this specific type of behavior during this same time period. Whoever had done one had probably done the rest.
When they placed Unterwegers timeline over that of the murders, and compared his MO in the Margaret Schaefer murder to the others, that clinched it. Added to that was an analysis done at the Los Angeles Crime Lab by criminalist Lynn Herold on the knots that had been used to tie the ligatures used to strangle the three prostitutes there. It was a complicated knot and it matched the pantyhose knots used on many of the victims in Austria
. The behavioral analysis appeared to be very strong.
Ligature with the same knot
In addition, although this would not enter the case in court, there was precedent of convicted felons who were born again with art who nevertheless returned to their old ways. Lets have a look.