U.S. Department of Justice
Office of Justice Programs

Bureau of Justice Statistics

Special Report
July 2002, NCJ 189100

Third-Party Involvement
in Violent Crime, 1993-99
By Mike Planty, Ph.D.
BJS Statistician
At least one other person besides a
lone victim and the offender(s) was
present at about two-thirds of violent
victimizations, according to estimates
from the National Crime Victimization
Survey (NCVS), 1993-99. In about 6.4
million violent victimizations annually a
third party was present. Less than a
quarter of these third parties were
victimized themselves.
Violent crime is often characterized as
an event occurring in isolation between
an offender and a victim. These
characterizations are often void of the
situational and social context in which
these events occur. Criminal incidents
may occur in the presence of or involve
persons in addition to a lone victim and
the offender(s).
These third parties may be victimized
themselves, witness the crime, intervene during the incident, and/or
escalate the violence of the incident.
(See page 7.) Third parties sometimes
choose not to become involved even
during an assault.
In addition to the third parties’
presence during incidents of violence,
they often serve as witnesses to criminal events. They may call the police,
provide information that helps to solve
crimes, clarify the characteristics of the
incident, or bear some responsibility
for the commencement or escalation

Highlights
About 66% of all violent crimes between 1993 and 1999 occurred in the
presence of someone in addition to the victim and offender(s).
Simple assault
Aggravated assault
Robbery
Rape/sexual assault
0%
25%
50%
75%
Percent of violent crimes
in which a bystander was present


 Third parties were present during

two-thirds of all violent victimizations
between 1993 and 1999. Third
parties were present at 70% of
assaults, 52% of robberies, and 29%
of rapes or sexual assaults.

 About a third of all intimate partner

violence occurred in the presence of
a third party compared to about twothirds of violence between strangers
or other acquaintances.

 Less than a quarter of third parties

present during a violent crime were
harmed or robbed themselves. Of all
violent victimizations 51% involved
only one victim and at least one third
party.

 Third parties were more likely to

help the situation than to make it
worse, but more often they did
neither. Victims stated that the
actions of third parties helped in

36% of violent victimizations,
worsened the situation in 11%, and
did neither in 44%.

 Third parties primarily helped by

preventing injuries. In 18% of cases
where a third party was present, the
actions of that person helped to
prevent injury, compared to 1% in
which the actions caused injury.

 On average each year, 1993-99,
third-party actions prevented injuries
in 1.2 million violent victimizations.

 In 38% of the victimizations in

which the third party helped, either
the victim escaped or the offender
was scared off.

 Violent victimizations at school or

occurring during leisure activities
away from home were the most likely
circumstances to involve the
presence of a third party.

Table 1. Third-party presence during
violent crime, 1993-99

Year
1993
1994
1995
1996
1997
1998
1999

Violent victimizations
Percent with
Total
third party
11,630,720
65.5%
11,583,370
66.4
10,225,170
67.4
9,543,460
66.0
9,023,510
66.5
8,548,450
65.8
7,473,880
65.6

of violence. Therefore, to better understand many violent crimes, it is necessary to account for persons present at
but often not directly involved in the
victimization.
This report uses data from the NCVS
to describe how often and under what
circumstances other people, in addition
to the victim interviewed and the
offender(s), are present during a
violent crime and their impact on the
outcome of these events.
A third party is an individual(s) other
than the victim interviewed and the
offender(s) who is present during a
violent crime. For example, a third
party may be another victim, a
bystander, an eyewitness, one who
intervenes, an instigator, another
household member, a police officer, or
some combination of the above. (For
The National Crime Victimization
Survey (NCVS)
The NCVS is the Nation's primary
source of information on the
frequency, characteristics, and
consequences of criminal victimization. One of the largest ongoing
household surveys conducted by the
Federal Government, the NCVS
collects information about crimes
both reported and not reported to
police.
The survey provides a national
forum for victims to describe the
impact of crime and the characteristics of violent offenders. This report
is one in an ongoing series using the
NCVS to inform topics of particular
interest. Previous reports in this
series and NCVS data are
presented on the BJS website at —
www.ojp.usdoj.gov/bjs/

Table 2. Third-party presence, by type of crime, 1993-99
Type of crime
Total
Rape/sexual assault
Robbery
Aggravated assault
Simple assault

All
9,718,370
393,200
1,088,390
2,074,940
6,161,830

Average annual violent victimizations
With a third party
Percent with third party
6,432,480
66.2%
114,160
29.0
560,080
51.5
1,471,630
70.9
4,286,610
69.6

more detailed information on the definition of a third party, see page 3.)

stabbed when they attempt to stop a
crime.

The NCVS cannot identify the true
intent of the offender. It does not
collect information on whether third
NCVS data show for 1993-1999, on
average, over 66% of all violent crimes parties present during the incident
involved someone besides the offender were targeted by the offender or
became involved in some other way.
and victim. The percentage of crimes
In addition, the NCVS does not record
involving a third party did not change
the number of third persons present
significantly from 1993 to 1999 (table
during the incident, only the number
1).
who were victimized.
Third parties were present most often
during aggravated (71%) and simple
When present during a violent incident,
assaults (70%) and less often during
third parties were not likely to be
rapes/sexual assaults (29%) (table 2).
harmed or robbed (table 3). While
About half of all robberies are commit- 66% of all violent victimizations
ted in the presence of a third party.
involved third parties, 15% involved
multiple victims. Of those incidents in
which a third party was present, 23%
Victimization of third parties
involved two or more victims: 14%
It is possible that third parties were also involved two victims, 4% three victims,
and 5% four or more victims.
the target of the violence, such as a
robber who victimized a group of
shoppers. In other cases the third
Of those victimizations involving third
party may have been harmed when he parties, the number of victims varied
by type of crime (table 4). Thirty-two
or she attempted to intervene. For
percent of aggravated assault incidents
example, third parties may be shot or
involving third parties resulted in
Presence of a third party

Table 3. Number of victims present in violent incidents,
by type of crime, 1993-99

Type of crime
Rape/sexual assault
Robbery
Aggravated assault
Simple assault
All violence

Total
100%
100
100
100
100

Percent of victimizations
Only victim One victim and
present
third parties
67.9%
25.7%
45.4
38.1
27.0
48.2
28.5
55.8
31.7
51.0

Multiple
victims
3.3%
13.3
22.7
13.7
15.2

Note: Detail may not add to total shown because of rounding. For each type of crime
there were 3% or less of victimizations with other or unknown configurations of victims.

Table 4. Number of victims in crimes with third-party presence,
by type of crime, 1993-99
Type of crime
Rape/sexual assault
Robbery
Aggravated assault
Simple assault
Total

Total
100%
100
100
100
100

Number of victims
1
2
3
4 or more
88.6%
7.5%
1.4%
2.5%
74.1
16.1
5.7
4.1
68.0
19.2
5.8
7.0
80.3
12.6
3.2
3.9
77.1
14.3
4.0
4.6

Note: Detail may not add to total shown because of rounding.

2 Third-Party Involvement in Violent Crime, 1993-99

Definition of a third party in the NCVS
A third party for this study is defined as any person at least age 12, other than
the victim interviewed and the offender, who was present during the victimization. Third parties may have been victimized during the incident and did not
necessarily intervene, physically or verbally. Third-party presence and the
actions of third parties are based on the victim’s perception of the events as
stated during the survey interview. These perceptions were influenced by the
victim’s ability to accurately recognize and recall the attributes of the incident.
For example, victims may have not been aware of the presence or actions
of other parties outside of their purview while the crimes were occurring.
Third parties include eyewitnesses, bystanders, instigators, interlopers, other
household members, and police officers. Third parties can be a single person
or a group. In some cases the victim may have been a third-party witness who
intervened and was then victimized. The NCVS does ask how many other
persons were victimized but does not count the number of third parties
present.
An incident may have multiple victims, including third parties age 12 or older
who were present during the incident and were either harmed or threatened
with harm.
To be considered “present,” the third party must have been at the immediate
scene of the crime during the incident. The opportunity for this person to be
attacked or threatened or to lose something by robbery or theft must have
been possible to consider the person present. The third party did not have to
be conscious or awake to be considered present. A third party not at the
scene of the crime but personally attacked or threatened with harm or subject
to attempted harm was considered present. These situations include being
shot at through a window by someone outside a building and being threatened
by a neighbor in the next yard but do not include threats not made in person,
such as over the telephone or through another person, the mail, or the
Internet.
Table 5. Number of offenders
and victims in violent crime, 1993-99
Lone Multiple
victim victims
Total
All violence
84.8% 15.2% 9,718,370
Lone offender
87.9
12.1 7,459,780
Multiple offenders 73.1
26.8 1,953,700

another person being harmed or
robbed, compared to 11% of rape/
sexual assaults. Compared to other
types of crime, assaults are significantly more likely to involve a third
party, and these persons are more
likely to be harmed.
In general, crimes with multiple offenders were more likely than singleoffender crimes to involve multiple
victims (table 5). Twenty-seven
percent of the victimizations involving
multiple offenders were associated with
multiple victims compared to 12% of
victimizations involving a single
offender.

Victim characteristics and thirdparty involvement

Table 6. Third-party presence
during violent crime, by victim
characteristics, 1993-99

Characteristic
Gender
Male
Female

Percent
Average
involving
annual
third
victimizations party
5,503,970
4,214,400

70.2%
60.9

Age
12-15
16-19
20-24
25-34
35-49
50-64
65 or older

1,601,170
1,549,050
1,478,070
2,159,370
2,195,480
583,540
151,680

74.5%
73.9
67.7
61.3
60.9
60.8
51.5

Marital status
Never married
Married
Divorced/separated
Widowed

5,528,240
2,431,880
1,606,570
118,300

69.7%
67.1
54.2
50.7

Race
White
Black
Other*
Hispanic

6,955,230
1,373,600
281,610
978,340

67.1%
63.4
62.4
64.0

Household income
Less than $7,500
$7,500-$14,999
$15,000-$24,999
$25,000-$34,999
$35,000-$49,999
$50,000-$74,999
$75,000 or more

1,117,260
1,286,180
1,468,080
1,344,010
1,447,470
1,251,110
846,120

60.7%
61.2
64.8
66.7
69.5
72.0
71.7

*In this report “other races” and “others” are
defined as Asians, Native Hawaiians, other
Pacific Islanders, Alaska Natives, and
American Indians and are considered
together.

Age of victim
The percentage of violent crimes
committed in the presence of someone
other than the victim and offender
varied by important victim characteristics (table 6).
Gender of victim
Males were more likely than females
to experience a violent crime in the
presence of a third party, 1993-99.
Seventy percent of all violent crime
involving male victims was committed
in the presence of another person
compared to 61% involving female
victims.

Younger persons were more likely to
experience violent victimization in the
presence of another party. Seventyfour percent of all violent crime experienced by victims age 12 to 19 involved
third parties, compared to 61% of
incidents with victims age 25 to 64
and 52% with victims age 65 or older.
Sixty-eight percent of all violence
experienced by victims age 20 to 24
occurred in the presence of a third
party.
Marital status
Married victims were as likely as those
who have never been married to have
a third party present during a violent
crime. Seventy percent of all violence
experienced by those never married

Third-Party Involvement in Violent Crime, 1993-99 3

Table 7. Third-party presence, by
victim-offender relationship, 1993-99

Table 9. Third-party presence,
by perceived alcohol/drug use by
offender during incident, 1993-99

Victim-offender Average annual Percent with
relationship
victimizations third-party
Stranger
4,560,520
70.4%
Intimates
1,044,540
35.6
Other
4,113,310
69.3
acquaintances

Perceived use Average annual Percent with
by offender
victimizations
third-party
Alcohol/drug
2,896,770
69.6%
No alcohol/drug
2,758,820
66.1
Do not know
3,945,100
65.2

Note: Table totals differ because some
respondents did not answer some questions.

Note: Table totals differ because some
respondents did not answer some questions.

Table 8. Third-party presence,
by perceived involvement of a gang
in the incident, 1993-99

Table 10. Third-party presence,
by weapon presence, 1993-99

Perceived gang Average annual Percent with
involvement
victimizations third-party
Gang-related
781,090
75.0%
Non-gangrelated
5,179,610
65.0
Unsure
3,538,030
68.1
Note: Table totals differ because some
respondents did not answer some questions.

occurred in the presence of a third
party compared to 67% of those who
were married. Divorced/separated and
widowed persons were less likely to
have another person present during
the violent event (54% and 51%,
respectively).

Presence of
Average
weapon during annual
crime
victimizations
No weapons
6,377,840
Weapon
2,533,530
Firearm
943,750
Knife
626,200
Other weapon
852,650
Unknown
110,930
Do not know if
807,000
offender armed

Percent
with thirdparty
66.7%
66.6
64.8
65.9
69.8
61.4
61.0

Note: Table totals differ because some
respondents did not answer some questions.

Offender characteristics and
third-party involvement

Table 11. Third-party presence
during violent crime, by situational
characteristic, 1993-99

Situational
characteristic
Locality
Urban
Suburban
Rural

Average
Percent
annual
with thirdvictimizations party
3,652,890
4,539,610
1,525,860

64.2%
67.3
67.8

Activity
Work
1,743,380
Traveling to or
from work
407,800
Shopping/errands
373,490
School
825,450
Traveling to or
from school
361,280
Leisure away
from home
2,206,740
Sleeping
206,920
Other home activity 1,940,090
Traveling to or
from other activity
876,540
Other
734,800

57.8
66.7

Time of incident
Day
Night

66.8%
66.0

5,104,030
4,489,870

74.5%
44.8
60.9
80.3
71.1
77.2
46.1
51.2

Note: Table totals differ because some
respondents did not answer some questions.

Sixty-four percent of violent crimes in
which the victim knew the offender
occurred in the presence of a third
party compared to 70% for violence
involving strangers (table 7). Intimate
partner violence occurred in the
presence of third parties 36% of the
time compared to 69% for non-intimate
violence.

present in 67% of violent incidents
involving a weapon or not.

In general, white victims experienced
violence more often in the presence of
a third party than victims of other
races. From 1993 to 1999, 67% of
violent victimizations experienced by
white victims occurred in the presence
of a third party compared to 63% for
Three-quarters of all gang-related inciblack victims, 64% for Hispanic victims, dents involved third parties compared
and 62% for victims of “other races.”
to 65% of non-gang violence (table 8).

The level of third-party involvement in
violent crime was greater in both rural
and suburban locations than in urban
areas (table 11). Sixty-four percent of
urban victims of violent crime reported
the presence of a third party compared
to 67% and 68% for suburban and rural
victims, respectively.

Household income

Third parties were more likely to be
present when the victim perceived that
the offender was using alcohol and/or
drugs during the incident (70%)
(table 9).

Victim activity

Race of victim

Overall the higher the person’s annual
household income, the greater the
likelihood that a third party was present
during the victimization. Third parties
were present at 61% of victimizations
in which the victim had an annual
household income of less than
$15,000, compared to 72% of victimizations of victims with annual household incomes of $50,000 or more.

Situational aspects of victimizations
involving third parties
Weapon use
Third parties were as likely to be
present at crimes in which someone
had a weapon 
 firearm, knife, or other
weapon 
 as they were to be at
incidents in which there was no
weapon (table 10). A third party was

4 Third-Party Involvement in Violent Crime, 1993-99

Urbanicity

The presence of third parties varied
depending on what the victim was
doing before the incident occurred.
School and leisure activities away from
home were the most likely activities to
include third parties when a victimization occurred.
Time of incident
The presence of a third party did not
vary by the time the incident occurred.
Both daytime and nighttime victimizations had a third party present about
66% of the time.

Table 12. Police notification and third-party presence, 1993-99

Table 13. Whether third-party
involvement helped or worsened
the situation, 1993-99

Percent of violent incidents
Average
Presence
Police
Police not Do not
annual
of third party notified notified
know
victimizations
Lone victim
40.6%
58.8%
0.6%
3,078,100
Third party
44.2
54.2
1.6
6,432,480
Do not know
37.0
60.5
2.4
106,460
Total
42.9
55.8
1.3
9,718,370

Third-party
involvement
Helped
Worsened
Both
Neither
Do not know

Note: Table totals differ because some respondents did not answer some questions.

Table 14. Whether third-party involvement helped or worsened the situation,
by type of crime, 1993-99
Type of
crime
Rape/sexual assault
Robbery
Aggravated assault
Simple assault
Total

Percent of violent incidents in which third party —
Do not
Total Helped Worsen
Both
Neither know
100%
33.4% 15.2%
0.9%
43.1%
7.4%
100
29.2
12.1
2.7
49.3
6.8
100
38.3
11.0
3.0
41.0
6.8
100
36.0
11.3
2.7
43.9
6.1
100
35.9
11.3
2.7
43.7
6.4

Average
annual
victimizations
114,160
560,080
1,471,630
4,286,610
6,432,480

Average annual
victimizations
2,306,210
729,850
176,670
2,811,160
408,600

Percent
total
35.9%
11.3
2.7
43.7
6.4

Note: Table totals differ because some
respondents did not answer some questions.

assaults. The percent of third parties
who made the situation worse did not
differ by type of crime.
Third parties helping the situation

A third party most often helped the
victim by preventing injury (47%) (table
15). This help resulted in 1.2 million
Third-party involvement and
victimizations annually, 1993-99, in
whether it helped or worsened the
which an injury or further injury to the
situation
victim was prevented. In 38% of the
cases in which the third parties helped,
For all types of crime, when third
either the victim escaped (20%) or the
parties were present, victims stated
offender was scared off (18%), totaling
that the third parties were more likely to 940,310 such victimizations annually.
help the situation (36%) than to make it Third-party actions also helped to
worse (11%), but most of the time they protect other people (9%) and property
did neither (44%) (table 13). In a small (3%).
number of cases, third parties both
helped and hurt the situation (3%).
Third parties worsening the situation

Note: Table totals differ because some respondents did not answer some questions.

Reporting to the police
The presence of a third party was
significantly related to whether the
police were notified (table 12). Police
notification occurred 41% of the time
when the victimization involved only the
victim versus 44% when the victimization occurred in the presence of a third
party. Police notification by the victim
or by someone else may occur during
the incident or hours or even days
later.
Table 15. How third-party
involvement helped or worsened
the situation, 1993-99
Victim opinion
of third-party
involvementa
Helped
Prevented injury
Scared offender off
Victim escaped
Protected property
Protected other people
Helped other ways
Worsened
Victim injured
More property loss
Others hurt worse
Offender got away
Made offenderangrier
Harmed other ways

Average
annual
victimizations

Percent
of total
with third
partyb

1,154,780
447,280
493,030
80,830
228,200
824,530

18.0%
7.0
7.7
1.3
3.5
12.8

69,120
14,230
44,420
12,010
559,280
275,980

1.1%
0.2
0.7
0.2
8.7
4.3

Note: Table totals differ because some
respondents did not answer some questions.
a
Victims could indicate more than one
category.
b
The numbers do not total to 100% because
the third party did not always help or worsen
the incident (43%) and victims could indicate
multiple categories.

The NCVS asks only about how the
actions of the third party either helped
or worsened the situation. It does not
gather information about the number of
third parties present who could have
intervened or about the characteristics
of those who did (or did not) intervene.
Third parties were more likely to help
the situation than to make it worse,
regardless of the type of crime (table
14). However third parties were less
likely to help the situation during
robberies (29%) compared to either
simple (36%) or aggravated (38%)

In cases when the victim stated that
third-party actions worsened the situation, usually the offender had become
angrier (62%). In 8% of these cases,
third-party actions resulted in victim
injury, and in 5%, in others being hurt
worse. In 30% of these cases the
victim was harmed in other ways.
In 18% of cases when a third party was
present the actions of this person
helped to prevent injury compared to
1% in which the actions caused victim
injury.

Table 16. Whether third-party involvement helped or worsened the situation,
by the presence of a weapon, 1993-99
Presence of
weapon during crime
Weapon
No weapon
Do not know

Percent of violent incidents in which third party —
Do not
Total Helped
Worsened Both Neither
know
100%
36.6%
11.1%
2.6%
43.2%
6.4%
100
36.3
11.7
2.8
43.9
5.4
100
29.7
9.0
2.7
43.8
14.7

Average
annual
victimizations
1,687,550
4,252,670
492,270

Note: Table totals differ because some respondents did not answer some questions.

Third-Party Involvement in Violent Crime, 1993-99 5

Intervention outcomes and incident
characteristics
When a third party was present, the
victim's perception varied as to whether
the third party helped or made the
situation worse.

Table 17. Whether third-party involvement helped or worsened the situation,
by victim-offender relationship, 1993-99
Victim-offender
relationship
Stranger
Intimates
Other acquaintances

Percent of violent incidents in which third party —
Do not
Total Helped
Worsened Both
Neither
know
100%
37.5%
10.3%
2.7%
43.1%
6.3%
100
35.4
11.5
2.3
43.9
6.9
100
34.0
12.5
2.9
44.4
6.3

Note: Table totals differ because some respondents did not answer some questions.

Weapons
There was no significant difference in
whether a third party either hurt or
helped the situation if the offender was
armed or unarmed (table 16). Third
parties helped in about 37% of cases
and hurt in 11%, but were most likely
to do neither (43%).
Victim-offender relationship
Victims perceived third-party involvement as more helpful in incidents
involving strangers than in victimizations in which the victims knew the
offenders (table 17). In addition, third
parties were more likely to make the

situation worse when the offender was
known to the victim than in a strangerrelated victimization. In either case
third parties were more likely to help
than make the situation worse, but
often did neither.
When intimate partner violence and
non-intimate violence is compared, the
results of third-party involvement did
not differ significantly. Third parties
helped in about 35% of these victimizations, made the situation worse in 12%
of the cases, and did neither in 44%.
In both cases, third parties were more
likely to help than hurt, but often did
neither.

Table 18. Whether third-party involvement helped or worsened the situation,
by location of victim’s residence, 1993-99

Location of
victim's residence
Urban
Suburban
Rural

Percent of violent incidents in which third party —
Average
Do not annual
Total Helped
Worsened
Both
Neither know
victimizations
100%
35.4%
10.8%
2.5%
44.2%
7.2%
2,343,820
100
36.2
11.4
2.7
43.8
5.3
3,053,440
100
34.1
12.5
3.5
42.3
7.7
1,025,220

Note: Table totals differ because some respondents did not answer some questions.

Table 19. Whether third-party involvement helped or worsened the situation,
by perceived gang involvement of the offender, 1993-99

Perceived
gang involvement
Gang-related
Non-gang-related
Do not know

Average
annual
victimizations
3,209,400
371,550
2,851,530

Percent of violent incidents in which third party —
Do not
Total Helped
Worsened Both
Neither
know
100%
36.1%
14.6%
4.2%
40.8%
4.2%
100
37.2
10.9
3.0
43.7
5.2
100
34.3
11.3
2.1
44.1
8.1

Average
annual
victimizations
585,590
3,365,130
2,409,370

Urbanicity
The outcome of third-party involvement
did not differ by the residential location
of the victim (table 18). Regardless of
location third parties helped the situation in about 35% of victimizations and
made it worse in about 11% of victimizations.
Gang-related incidents
The percent of victimizations that were
helped by third-party involvement did
not differ significantly based on
offender gang membership (table 19).
However if the offender was in a gang
third parties were likely to make the
situation worse. In all instances, third
parties were more likely to help than to
make the situation worse, but most did
neither.
Offender alcohol/drug use
When the victim perceived the
offender to be under the influence
of alcohol and/or drugs during the
incident, third parties were more likely
to help the situation than to make it
worse or to have no impact (table 20).
In these incidents, third-party actions
were more likely to help the situation
or to make the situation worse
compared to incidents in which the
offender was not under the influence
of alcohol and/or drugs.

Note: Table totals differ because some respondents did not answer some questions.

Survey methodology
Table 20. Third-party involvement and incident outcomes,
by offender alcohol and drug use, 1993-99

Perceived use
by offender
Alcohol/drug
No alcohol/drug
Do not know

Percent of violent incidents in which third party —
Do not
Total Helped
Worsened Both
Neither
know
100%
42.4%
12.6%
4.1%
35.6%
5.3%
100
34.5
10.5
2.4
47.8
4.8
100
31.8
11.0
2.0
47.2
8.1

Average
annual
victimizations
2,017,230
1,824,530
2,571,380

Note: Table totals differ because some respondents did not answer some questions.

6 Third-Party Involvement in Violent Crime, 1993-99

This Special Report presents data on
rape, sexual assault, robbery, aggravated assault, and simple assault from
the National Crime Victimization
Survey (NCVS). The NCVS gathers
data on crimes against persons age 12
or older, reported and not reported to
the police, from a nationally representative sample of U.S. households. The
NCVS provides information about
victims (age, gender, race, ethnicity,

marital status, income, and educational
level), offenders (gender, race,
approximate age, and victim-offender
relations) and the nature of the crime
(time and place of occurrence, use of
weapons, nature of injury, and
economic consequences).
Between 1993 and 1999 approximately
336,300 households and 651,750
individuals age 12 or older were interviewed. For the NCVS data presented,
response rates varied between 93%
and 96% of eligible households and
between 89% and 92% of eligible
individuals.
In some instances the sample size
used to generate an estimate is small.
While the estimate is reliable, it is also
likely associated with a relatively large
confidence interval and should be
viewed with caution.
Standard error computations
Comparisons of percentages and rates
made in this report were tested to
determine if observed differences were
statistically significant. Differences
described as higher, lower, or different
passed a hypothesis test at the .05
level of statistical significance (95%
confidence level). The tested difference was greater than twice the
standard error of that difference.
For comparisons that were statistically
significant at the 0.10 level (90% confidence level), “somewhat,” “slightly,” or
“marginally” is used to note the nature
of the difference.
Caution is required when comparing
estimates not explicitly discussed in
this Special Report. What may appear
to be large differences may not test as
statistically significant at the 95% or the
90% confidence level. Significance
testing calculations were conducted at
the Bureau of Justice Statistics using
statistical programs developed specifically for the NCVS by the U.S. Bureau
of the Census. These programs take
into consideration many aspects of the
complex NCVS sample design when
calculating generalized variance
estimates.

Further reading on third parties and crime

 Richard Felson and H. S.

Steadman, “Situations and Processes
Leading to Criminal Violence,” Criminology, 26, 1983, pp. 59-74.

 Leslie Kennedy and David Forde,

When Push Comes to Shove: A
Routine Conflict Approach to
Violence, Albany, NY: State University
of New York Press, 1999.

 B. Latane and S. Nida, “Ten Years
of Research on Group Size and
Helping,” Psychological Bulletin, 89,
1981, pp. 308-324.

 A. M. Rosenthal, Thirty-eight

Witnesses, New York: McGraw Hill,
1964.

 R. L. Shotland and L. I. Goodstein,

“The Role of Bystanders in Crime
Control,” Journal of Social Issues, 40,
1984, pp. 9-26.

 Samantha Wells and Kathryn

Graham, “The Frequency of ThirdParty Involvement in Incidents of
Barroom Aggression,” Contemporary
Drug Problems, 26, 1999, pp.
457-480.

Sexual assault includes a wide range
of victimizations, distinct from rape or
The NCVS data have a number of data attempted rape. These crimes include
collection procedures to consider when completed or attempted attacks generally involving unwanted sexual contact
discussing violent crime. The victims
between the victim and offender.
recall the incidents and the data are
not verified through other data sources. Sexual assaults may or may not
involve force and include such things
Victims do not report many of these
as grabbing or fondling. Sexual
incidents to law enforcement officials.
The survey relies on the victim’s ability assault also includes verbal threats.
to recall accurately the characteristics
Robbery is a completed or attempted
of each incident.
theft directly from a person, of property
The NCVS treats six or more incidents or cash by force or threat of force, with
similar in nature, for which the victim is or without a weapon, and with or
unable to furnish the specific details for without an injury.
each incident separately, as “series
Aggravated assault is a completed or
data.” Only the incident information
attempted attack with a weapon,
about the most recent incident is
regardless of whether or not an injury
collected, and the NCVS counts the
occurred. It is also an attack without a
series as one victimization.
weapon in which the victim is seriously
Violent crime is defined in this report as injured.
attempted or completed rape, sexual
Simple assault is an attack without a
assault, robbery, aggravated assault,
and simple assault. Definitions used in weapon resulting either in no injury,
minor injury (such as bruises, black
this report are as follows:
eyes, cuts, scratches, or swelling), or
an undetermined injury requiring less
Rape is forced sexual intercourse,
than
2 days of hospitalization. Simple
including both psychological coercion
assaults
also include attempted
and physical force. Forced sexual
assaults
without
a weapon.
intercourse means vaginal, anal, or
Definitions

oral penetration by the offender(s).
This category includes incidents where
the penetration is from a foreign object
such as a bottle. This definition
includes attempted rapes, male and
female victims, and heterosexual and
homosexual rape.

Third-Party Involvement in Violent Crime, 1993-99 7

This report and the data that it analyzes are available on the Internet
through <www.ojp.usdoj.gov/bjs>.

The Bureau of Justice Statistics
is the statistical agency of the
U.S. Department of Justice.
Lawrence A. Greenfeld is
acting director.
BJS Special Reports address a
specific topic in depth from one or
more datasets that cover many
topics.
Mike G. Planty wrote this report
under the supervision of Michael
Rand. Timothy C. Hart provided
statistical assistance and verification.
Callie Marie Rennison reviewed the
report and prepared it for release.
Tom Hester edited the report. Jayne
Robinson prepared the report for
publication.
July 2002, NCJ 189100

8 Third-Party Involvement in Violent Crime, 1993-99