Psychopathy-associated personality traits influence crime-scene behavior in male homicide offenders

Figures & data

Table 1. Characteristics of 72 male homicide offenders and index offenses.

		Manner		Motive
	All	Instrumental	Expressive	Intimate-partner or family-related	Altercations	Robberies or burglaries	Criminal conflicts	Sexual homicides
Parameter	n = 72^a	n = 18	n = 54	n = 12	n = 37	n = 6	n = 12	n = 5
Demographic
Age at index offense in years, mean (range)	33 (19–63)	32 (19–45)	33 (19–63)	36 (28–63)	32 (19–63)	36 (21–44)	30 (19–45)	32 (27–43)
Place of birth (n = 69), % (n)		n = 15	n = 53			n = 5	n = 9
Sweden	78 (54)	87 (13)	75 (40)	75 (9)	76 (28)	80 (4)	89 (8)	80 (4)
Abroad	22 (15)	13 (2)	25 (13)	25 (3)	24 (9)	20 (1)	11 (1)	20 (1)
Previous criminal conviction (n = 70), % (n)			n = 49	n = 11	n = 36
Yes	91 (64)	95 (17)	96 (47)	82 (9)	92 (33)	83 (5)	100 (12)	100 (5)
No	9 (6)	6 (1)	4 (2)	18 (2)	8 (3)	17 (1)	0 (0)	0 (0)
Previous conviction for violent offense (n = 67), % (n)		n = 15	n = 52		n = 36	n = 4	n = 10
Yes	57 (38)	73 (11)	52 (27)	17 (2)	64 (23)	50 (2)	80 (8)	60 (3)
No	43 (29)	27 (4)	48 (25)	83 (10)	36 (13)	50 (2)	20 (2)	40 (2)
Crime-scene behavior
At least one co-offender, % (n)
Yes	17 (12)	28 (5)	13 (7)	0 (0)	14 (5)	33 (2)	42 (5)	0 (0)
No	83 (60)	72 (13)	87 (47)	100 (12)	86 (32)	67 (4)	58 (7)	100 (5)
Offender intoxicated (n = 69), % (n)		n = 15					n = 9
Yes	80 (55)	80 (12)	80 (43)	67 (8)	86 (32)	83 (5)	67 (6)	80 (4)
No	20 (14)	20 (3)	20 (11)	33 (4)	14 (5)	17 (1)	33 (3)	20 (1)
Sex of index victim, % (n)^b
Female	24 (17)	33 (6)	20 (11)	75 (9)	5 (2)	17 (1)	8 (1)	80 (4)
Male	76 (55)	67 (12)	80 (43)	25 (3)	95 (35)	83 (5)	92 (11)	20 (1)
Index victim intoxicated, % (n)^b						n = 6
Yes	69 (50)	56 (10)	74 (40)	58 (7)	76 (28)	50 (3)	75 (9)	60 (3)
No	31 (22)	44 (8)	26 (14)	42 (5)	24 (9)	50 (3)	25 (3)	40 (2)
Method of violence (n = 71), % (n)			n = 53		n = 36
Sharp-force trauma	42 (30)	28 (5)	47 (25)	33 (4)	58 (21)	33 (2)	8 (1)	40 (2)
Blunt-force trauma	17 (12)	28 (5)	30 (16)	42 (5)	25 (9)	33 (2)	42 (5)	0 (0)
Gunshot trauma	30 (21)	22 (4)	15 (8)	17 (2)	11 (4)	7 (1)	42 (5)	0 (0)
Asphyxia	7 (5)	22 (4)	2 (1)	8 (1)	0 (0)	17 (1)	0 (0)	60 (3)
Other	4 (3)	0 (0)	6 (3)	0 (0)	6 (2)	0 (0)	8 (1)	0 (0)

^a Unless otherwise indicated in the case of missing data.

^b Chronologically first victim in the case of multiple victims.

Table 2. Mean total Psychopathy Checklist – Revised (PCL-R) scores and mean scores on component factors 1 and 2, after categorization of 72 male homicide offenders according to motive and manner.

	PCL-R, mean score (SD; range)
	Total	Factor 1	Factor 2
Manner
Instrumental (n = 18)	22.1 (9.2; 4.0–39.0)	9.8 (4.2; 0.0–16.0)	10.9 (5.5; 0.0–20.0)
Expressive (n = 54)^a	15.4 (10.4; 0.0–35.0)	5.1 (4.5; 0.0–14.0)	9.2 (6.3; 0.0–20.0) (n = 53)
Motive
Intimate-partner or family-related (n = 12)^a	9.0 (9.4; 0.0–32.5)	3.3 (4.0; 0.0–14.0)	3.7 (4.2; 0.0–12.0) (n = 11)
Altercations (n = 37)	17.6 (10.1; 1.0–35.0)	5.8 (4.6; 0.0–14.0)	10.8 (6.1; 0.0–20.0)
Robberies or burglaries (n = 6)	17.3 (10.4; 4.0–29.0)	8.7 (5.2; 0.0–14.0)	8.0 (6.4; 0.0–17.0)
Criminal conflicts (n = 12)	19.2 (9.7; 5.3–39.0)	6.8 (4.5; 0.0–16.0)	11.2 (5.2; 1.1–20.0)
Sexual homicides (n = 5)	27.3 (7.1; 17.0–37.0)	12.6 (2.3; 9.0–15.0)	12.2 (5.1; 6.0–19.0)

^a Unless otherwise indicated in the case of missing data.