An examination of behavioral consistency using individual behaviors or groups of behaviors in serial homicide

Abstract

Establishing behavioral consistency in serial homicide offending behavior is essential when linking homicides together and to a common offender. An examination of 35 serial homicide behaviors utilized by 90 offenders in 450 serial homicide cases was carried out to identify whether these offenders consistently performed the same behaviors across their series of homicides and whether it is more effective to examine individual behaviors or groupings of behaviors in order to identify behavioral consistency. This study provides the first empirically based evidence testing the use of using single behaviors as linking factors in linking homicide cases in a series, and shows that this method has inherent difficulties in accomplishing this, thus providing the first wave of empirical testing that questions current theories in the literature on serial homicide, which has suggested that signatures or specific key behaviors are important in understanding the consistency in an offender's behavior across the crimes. Recommendations for future studies on linking using signatures are suggested, including a more in-depth qualitative empirical evaluation of individual series.

Incorporating context in linking crimes: an exploratory study of situational similarity and if‐then contingencies

“…Behaviours that are cognitively mediated are hypothesised to show less cross-situational consistency because the demands made by the situation become less important (Shoda, Mischel, & Wright, 1993). If victim resistance was considered a situational feature that might cause an offender negative affect or stress, this might partly explain why greater consistency has been observed in control behaviours in serial stranger sex offences, homicide, and robbery (Bateman & Salfati, 2007;Grubin, Kelly, & Brunsdon, 2001;Woodhams & Toye, 2007;. Evidence from personality psychology for the mediation effect of automatic versus cognitively mediated behaviours is, however, mixed (Furr & Funder, 2004).…”

“…Behavioural consistency in control behaviours has now been investigated for serial robbery, rape, and homicide (e.g. Bateman & Salfati, 2007;Grubin, Kelly, & Brunsdon, 2001;Woodhams & Toye, 2007), and thus control appears to be one domain that is shared by more than one offence type. Such an analysis was beyond the scope of the current paper due to the available data set, but this research question would benefi t from exploration in the future.…”

The consistency of inconsistency in serial homicide: patterns of behavioural change across series

“…behavioural consistency). Recent empirical studies (Bateman & Salfati, 2007;Salfati & Bateman, 2005) have found little evidence of consistency looking at either individual, group or themes of behaviours in serial homicide. Several factors have been proffered to explain the inconsistencies in offenders' behaviours, such as maturation, development, and learning (Canter & Youngs, 2003;Salfati, 2008).…”

Rape and sexual assault in investigative psychology: the contribution of sex offenders' research to offender profiling

“…Although several studies successfully identifi ed evidence of consistency across series of sexual crimes for linkage purposes (Bateman & Salfati, 2007;Canter, Heritage, Wilson, Davies, Kirby, Holden, McGinley, Hughes, Larkin, Martin, Tsang, Vaughan, & Donald, 1991;Grubin, Kelly, & Brunsdon, 2001;Salfati & Bateman, 2005;Santtila, Junkkila, & Sandnabba, 2005;Woodhams, Grant, & Price, 2007a), Woodhams, Hollin, and Bull (2008) found little support for consistency in cases of serial sexual assaults using if-then contingencies. Interestingly, fi ndings from sex offender and profi ling research point towards the same direction, suggesting that these offenders display both consistency and versatility depending on the situation, as well as the specifi c actions, observed.…”