1. Criminal Violence: Patterns, Causes, and Prevention Riedel and Welsh, Ch. 4 “Homicides and Assaults”

2. Homicides and Assaults in the U.S. Patterns and Trends Explanations
OUTLINE
Homicides and Assaults in the U.S.
Patterns and Trends
Explanations
Interventions

3. Definitions
Murder and Non-negligent Manslaughter (UCR): the “willful (non-negligent) killing of one human being by another.”
Aggravated Assault (NCVS): "attack or attempted attack with a weapon, regardless of whether an injury occurred or not, as well as an attack without a weapon when serious injury resulted."
Simple Assault: does not involve a weapon; does not result in serious injury to the victim

4. Homicide Patterns (UCR): 2008
VICTIMS
Gender: 78.0% of victims were male
Race: % of victims were black, 48.2% white, 2.3% “other”
Victim/offender relationship:
9.4% of victims were killed by intimate partners
8.1% of victims were killed by other family members
12.3% were murdered by strangers
26.0% were slain by acquaintances (neighbor, friend, employee, etc.)
OFFENDERS
Gender: 64.9% of offenders were males. 
Race: 36.5% of offenders were black, 32.8% were white, and 1.7% were “other”
INCIDENTS
Firearms: 66.8% of the offenses involved firearms
Setting:
28.9% of victims were murdered during arguments
20.6% were killed in conjunction with a felony (rape, robbery, etc.)
Circumstances unknown for 35.3% of reported homicides

5. Homicide Rates in the United States, 1960-2008
Year
Homicide Rate per 100,000
Figure 4.1
Homicide Rates in the United States,
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
4.5 5
5.5 6
6.5 7
7.5 8
8.5 9
9.5 10
10.5
Source:
Sourcebook of Criminal Justice Statistics.

6. Table 1. Rates of violent crime, by gender, race, Hispanic origin, and age of victim, 2008
Violent victimizations per 1,000 persons age 12 or older
Demographic
characteristic of victim
Population
All
Rape/sexual assault
Robbery
All assault
Aggravated
assault Simple assault
Gender
Male
123,071,020
21.3
0.3^
2.7
18.3
3.9
14.5
Female
129,171,510
17.3
1.3
1.7
14.3
2.8
11.5
Race White
204,683,500
18.1
0.6
1.6
15.9
3.0
12.8
Black
30,709,860
25.9
1.9^
5.5
18.5
5.2
13.3
Other race*
13,952,240
15.2
0.9^
3.0^
11.3
8.5
Two or more races
2,896,930
51.6
6.8
42.9
36.1
Hispanic origin
Hispanic
34,506,680
16.4
0.6^
3.4
12.4
3.5
8.9
Non-Hispanic
217,351,750
19.7
0.8
2.0
16.9
3.3
13.6
Age
12-15
16,414,550
42.2
1.6^
35.2
6.1
29.0
16-19
17,280,270
37.0
2.2
4.8
30.0
5.6
24.5
20-24
20,547,620
37.8
2.1
5.4
30.3
8.7
21.5
25-34
40,649,500
23.4
0.7
2.3
20.5
4.0
16.5
35-49
65,123,030
16.7
1.9
14.1
11.4
50-64
55,116,320
10.7
0.2^
9.7
7.7
65 or older
37,111,240
3.1
0.4^
Note: Violent crimes measured by the National Crime Victimization Survey include rape, sexual assault, robbery, and aggravated and simple assault. Because the NCVS interviews persons about their victimizations, murder and manslaughter cannot be included.
^Based upon 10 or fewer sample cases. N
*Includes American Indians, Alaska Natives, Asians, Native Hawaiians, and other Pacific Islanders.

7. Table 2 Property crime rates, by household income and household size, 2008 (Burglary, Motor Vehicle Theft, and Theft) .
Characteristics of household
Number of households
Total Victims
Household income
Less than $7,500
4,115,470
204.2
$7,500-$14,999
6,361,960
175.0
$15,000-$24,999
9,412,930
161.7
$25,000-$34,999
9,901,970
150.5
$35,000-$49,999
13,497,280
142.7
$50,000-$74,999
14,601,440
125.8
$75,000 or more
24,115,150
133.4
Number of persons in household 1
34,561,280
100.3
2 or 3
60,022,010
122.2
4 or 5
22,868,210
197.0
6 or more
3,689,560
273.9

8. Explanations Symbolic interaction theory
Both homicides & aggravated assaults tend to result from an escalation of interpersonal conflict [see Luckenbill].
Both tend to have similar situational dynamics:
Both tend to occur between people who know one another, especially during an argument or fight.
Violence is often goal-oriented behavior: "to compel or deter others, to achieve a favorable social identity, and to obtain justice, as defined by the actor."

9. Explanations (cont.)
Subcultural theories: values and beliefs that sanction violence as problem-solving behavior within certain groups (e.g., gangs)
The subculture of violence suggests that lower- or working-class youths more frequently see violence as a way to solve personal problems.

10. Interventions
Q: What explanations have been offered for declines in homicide and aggravated assaults since 1993?
Decline in high-risk age group (15-24)
Decline in handgun homicide
Drug markets stabilized
Increase in legitimate and decrease in illegitimate opportunities
Increased use of incarceration
Decline in partner homicides
Violence prevention programs (e.g., mediation)

11. Arrest Clearances
Definition: An act is considered cleared when “at least one person is arrested, charged with the commission of an offense, and turned over to the court for prosecution…” (FBI)
Arrest clearances for homicides have declined linearly from 92.3% in 1960 to 63.6% in 2008.
Why Are Arrest Clearances Important?
Without arrest, no further processing of offenders
Without arrest, offenders are free to offend again
No arrest further traumatizes victim and family
Low clearance rates undermine morale of law enforcement
Low clearance rates mean less information on offenders for research

12. Arrest Clearances (cont.)
Type of homicides cleared
Homicides with female victims more likely to be cleared
White victim homicides are more likely to be cleared, although the research results are mixed
Young homicide victims are more easily cleared
Non-gun homicides are cleared more quickly
Homicides involving domestic and intimate partner relationships are cleared more readily

13. Explanations and Interventions
Do police investigate all homicides equally diligently or do they exercise discretion by race, gender, age, etc. of victim?
Drawing from Donald Black’s theory, Litwin and associates found mixed results
Interventions
Cold case squads continue the investigation of homicides after the usual amount of time devoted to clearing has passed
Vicodq Society provides support to cold case investigations

14. Serial Homicides and Mass Murders
Serial homicides: multiple killings by the same person over a period of time, usually months or years
Mass murder: single event or several killings in a very brief period -- “spree killing.”
Prior to 1980s, inflated estimates resulted from invalid practice of attributing all homicides with “unknown” circumstances to serial killings.
FBI Estimates: about 127 serial homicide victims/year, about 10 offenders operating at any one time.
Psychological appearance: “extraordinarily ordinary”
Fox & Levin: serial killers kill for thrills, sexual satisfaction, or feelings of dominance and control-- more “cruel” than “crazy.” Some are sociopaths, but show affection toward family members & friends.

15. Serial Homicides
Victims: often vulnerable (e.g., elderly, transients, prostitutes, runaways, hospital patients) people who may not be quickly missed
Offenders: Hickey identified 337 male (83%) and 67 female (17%) serial killers responsible for 2,526 homicides between 1800 and 1995.
Whites: 80% of all serial killers. Majority tend to operate in one city or even one neighborhood.
Trends: Serial homicides may have increased over time.
35% of the killers in sample were identified between 1950 and 1974
45% of the killers were identified between 1975 and 1995

16. Explanations Interventions
Little research supports any one cause consistently.
Biological: XYY, neurotransmitters, hormonal imbalances
Psychological: psychosis, dissociative disorders, personality disorders, psychopathy
Sociological: anonymity and normlessness (anomie), child abuse, labeling, lack of social bonds
But: huge number of “false positives” (i.e., many normal people have one or more of these characteristics and are not serial killers, or even violent, or even criminals)
Interventions
Law enforcement approaches include interagency communication, geographic analysis, and profiling (look for patterns in incidents, victims, places).
Example: DC snipers