This chapter is based on a number of research projects on offender profiling and homicidal crime scene behavior carried out at the Finnish National Bureau of Investigation. This specific study investigated homicidal strangulation in Finland during a 7-year period and analyzed and compared offense and offender characteristics in manual and ligature strangulation cases. The
results diverge in many respects from the previous research findings attributed to homicidal strangulation and emphasize the need to identify possible culture-specific patterns and psychopathological offender characteristics in homicidal behavior.
Homicidal strangulation accounts for approximately 10–20% of all homicidal deaths in various countries (1–4). In strangulation, the cause of death is cerebral hypoxia secondary to compression and thereby an occlusion of the vessels supplying blood to the brain (5). It has been estimated that applying pressure on the neck causes unconsciousness in approximately 5–15 seconds (6–8). Homicidal strangulation can be made manually or by using a ligature. In ligature strangulation, pressure on the neck is applied by a constricting band (e.g., belt, electric cord, rope) that is tightened by some force other than the body weight. In manual strangulation, pressure is applied by hand, forearm, or other limb. Research results regarding which one of the homicidal strangulation methods is more frequent are mixed (6,9–11).
Research on homicidal strangulation has shown that in a high percentage
of cases, the offender and the victim have a family relationship (1,9,12) and
that as much as 75% of the victims are females and infants (1,9,11–13). In
previous studies, the most frequent motives for homicidal strangulation have
been rape (6), sexual jealousy, and personal rivalry (9,11). Predomination of female victims in homicidal strangulation has been explained by quarrels in relationships and unrehearsed violence applied by bare hands as well as by physical disadvantage and incapability of resistance of female victims 9,11,14). The latter rationale has been explicated relative to homicides by firearms. Fisher et al. (14) cite Dotzauer and Jarosch (15), who suggest that firearms are more frequently used against male victims, because they permit the offender to keep a greater distance from the victim, whose physical strength may be feared.
It has also been suggested that females predominate as victims in
homicidal strangulation, because they are more likely to be targets of sexual
assaults, and strangulation may occur to overcome their resistance during the
sexual act (1). In previous studies, strangulation has been firmly associated with sexual and sadistic murders (16–19). Strangulation has been found to be the cause of death in 67% of sexual murders (20), 63% of sexual murders of elderly females (21), 61% of sexual sadistic murders (22), and 59% of serial sexual murders (19). Furthermore, Gratzer and Bradford (23) studied three samples of sexual offenders, and their results indicated that strangulation, particularly by a ligature, is more frequent in sexual sadistic than nonsadistic murders. However, ligature strangulation accounted only for 20% of the causes of death in sexually sadistic murders; blunt force trauma and stabbing were both more frequent causes of death. In a study on sexual murder, Kocsis et al. (24) analyzed crime scene behavior and provided an empirical model with distinct behavior clusters. Their study suggested that in sexual murders, ligature strangulation is associated with deliberate and cruel crime scene behavior, suggesting a “predator” murder pattern.
Predomination of strangulation as a cause of death in sexual and sadistic
murders has been interpreted in various ways. Based on his clinical work with
sexual murderers, Brittain (25) suggested that for the sadistic murderer, the
method of killing is almost always asphyxial. It may be due to the positions
of the murderer and his victim in a sexual attack, which, according to Brittain,
makes strangulation an “easy and convenient” way of killing and prevents
the victim from crying out. Furthermore, both Brittain (25) and Gratzer and
Bradford (23) concluded that the offender is able to exert greater control and
power over the victim by strangulation.