Testing the Cuckoldry Risk Hypothesis of Partner Sexual Coercion in Community and Forensic Samples

Evolutionary Psychology
www.epjournal.net – 2009. 7(2): 164-178
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Original Article
Testing the Cuckoldry Risk Hypothesis of Partner Sexual Coercion in
Community and Forensic Samples
Joseph A. Camilleri, Psychology Department, Westfield State College, Westfield, USA. Email:
jcamilleri@wsc.ma.edu (Corresponding author).
Vernon L. Quinsey, Department of Psychology, Queen’s University, Kingston, Canada.
Abstract: Evolutionary theory has informed the investigation of male sexual coercion but
has seldom been applied to the analysis of sexual coercion within established couples. The
cuckoldry risk hypothesis, that sexual coercion is a male tactic used to reduce the risk of
extrapair paternity, was tested in two studies. In a community sample, indirect cues of
infidelity predicted male propensity for sexual coaxing in the relationship, and direct cues
predicted propensity for sexual coercion. In the forensic sample, we found that most partner
rapists experienced cuckoldry risk prior to committing their offence and experienced more
types of cuckoldry risk events than non-sexual partner assaulters. These findings suggest
that cuckoldry risk influences male sexual coercion in established sexual relationships.
Keywords: cuckoldry risk, partner sexual coercion, partner rape.
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Introduction
Partner sexual coercion poses a unique problem for evolutionary theories about
rape. Goetz and Shackelford (2006) argued that partner rape is inconsistent with the
conceptualization of rape as either an adaptation to increase reproductive success through
forced mateships with multiple partners, or as a byproduct of selection to prefer multiple
partners (e.g., Palmer, 1991; Shields and Shields, 1983; Thornhill and Palmer, 2000;
Thornhill and Thornhill, 1983), because partner rape does not increase partner number. The
theoretical solution to this problem requires moving beyond non-partner rape hypotheses
by examining the function of sexually coercive tactics in relationships.


Function of partner sexual coercion
The idea that partner sexual coercion is a response to cuckoldry has been proposed
elsewhere (Buss, 2003; Camilleri, 2004; Goetz and Shackelford, 2006; Goetz, Shackelford,
and Camilleri, 2008; Lalumière, Harris, Quinsey, and Rice, 2005; Quinsey and Lalumière,

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Partner sexual coercion and cuckoldry risk
1995; Thornhill and Palmer, 2000; Wilson and Daly, 1992), and is consistent with sperm
competition theory. This theory posits that, in species where females mate with more than
one male during the same fertile cycle, morphological and behavioral traits that reduce
risks of cuckoldry resulting from such competition are selectively advantageous (Birkhead,
2000). Lalumière et al. (2005), for example, reviewed how in some polygamous species,
males produce more sperm in the presence of other males (e.g., beetles and crabs) and force
copulation if the male returns to see another male near his partner, as, for example in
mallards.
Sperm competition can also exist in socially monogamous species where extra pair
copulations occur (Griffith, 2007; Westneat and Stewart, 2003), and there is ample
evidence that humans have such a mating system. For example, 20% to 40% of American
women report having cheated on their partner, and prevalence estimates of offspring from
extra-pair copulations range from 1% to 30% across cultures, averaging around 10%
(reviewed in Buss, 2000, 2003; Shackelford, Pound, Goetz, and LaMunyon, 2005).
Johnson and colleagues (2001) also found that 9% of all women and 15% of women
between the ages of 16 and 24 years reported having concurrent sexual relationships, and
Gallup, Burch, and Berens Mitchell (2006) found 25% of women in a college sample
reported at least one extra-pair copulation. Genetic studies have shown that promiscuity
and sociosexuality in humans have heritable components (Bailey, Kirk, Zhu, Dunne, and
Martin, 2000; Lyons et al., 2004) and there is some evidence for a genetic contribution to
variability in female infidelity (Cherkas, Oelsner, Mak, Valdes, and Spector, 2004). These
findings support hypotheses that suggest extra-pair copulation by women is an adaptive
characteristic (Thornhill and Gangestad, 2008).
Because cuckoldry is a real risk to men’s reproductive fitness, sperm competition
may account for certain sex differences in human psychology and morphology. Thus far,
the influence of sperm competition in humans has been studied in terms of sexual interest
(Pound, 2002), attraction and interest in a sexual partner (Shackelford et al., 2002), sexual
behaviors (Shackelford, Pound, and Goetz, 2005), mate retention (Starratt, Shackelford,
Goetz, and McKibbin, 2007), and penis morphology (Gallup et al., 2003). Partner sexual
coercion is understood as another possible adaptation to sperm competition (for a more
comprehensive review of the human sperm competition literature, see Shackelford, Pound,
Goetz, and LaMunyon, 2005).
There is some evidence supporting the idea that partner sexual coercion is a
response to cuckoldry risk. Shields and Hanneke (1983) found that 47% of women who
were beaten and raped by their husband reported having had sex with another man, whereas
only 23% of those beaten but not raped and 10% of nonvictimized wives admitted to
engaging in such behavior. Although these differences are consistent with the cuckoldry
risk hypothesis, their causal status remains unclear. Goetz and Shackelford (2006) directly
tested partner sexual coercion as a sperm competition tactic, finding a correlation between
past sexual coercion and perceived partner infidelities. Even though their study provided
the first direct evidence for the cuckoldry risk hypothesis for partner sexual coercion, there
are several components of that hypothesis that require further investigation. We outline
these components in the following sections.



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Sex specificity
Differential sexual selection implies the presence of a characteristic in one sex but
not the other. In some cases, different selection pressures between the sexes results in
similar psychological phenotypes (e.g., Shackelford, Goetz, LaMunyon, Quintus, and
Weekes-Shackelford, 2004), but psychological mechanisms shaped by sexual selection are
typically sex-specific. Unlike studies that asked men about perpetration and women about
victimization (e.g., Goetz and Shackelford, 2006), we were interested in asking men and
women questions about perpetration because if partner sexual coercion in response to
cuckoldry risk is a male-specific mechanism, we should not observe this relationship
among women. This design provides an important means for falsifying this hypothesis. In
each test of the cuckoldry risk hypothesis, we predicted that the relationship between
cuckoldry risk and sexual coercion would be found among men, not among women.

Temporal sensitivity to cuckoldry risk

A correlation between past instances of cuckoldry risk and a history of sexually
coercive behavior does not entirely address the facultative function of a cuckoldry risk
mechanism. Considering the potential costs of sexually coercive behavior (e.g., substantial
physical injury resulting in pregnancy difficulties or dissolution of the relationship), use of
such a tactic should only take place in response to a recent and substantial risk of
cuckoldry. This is consistent with the intra-pair proclivity model of female infidelity
(Gallup and Burch, 2006; Gallup, Burch, and Berens Mitchell, 2006), which predicts
heightened male sexual interest immediately after female infidelity. Thus, tests of the
temporal sensitivity of the cuckoldry risk mechanism are required. We therefore predicted
that men who are currently at risk of cuckoldry should exhibit a greater interest in using
sexual coercion to obtain sex from their partner than men who are not currently at risk.

Variability in severity
Due to the costs associated with severe forms of sexual coercion, men may use
more subtle strategies to obtain sex from a reluctant partner (Goetz and Shackelford, 2006).
Thus, men should use severe forms of coercion either when cuckoldry is known, or as a last
resort with a partner who decides to leave or already left the relationship. Otherwise, less
severe tactics—we will refer to them as sexual coaxing (i.e. noncoercive tactics used for
sexual persuasion)—may be used when cuckoldry is suspected or when circumstances have
increased the risk of cuckoldry (for further discussion on the differences between sexual
coercion and sexual coaxing, see Camilleri, Quinsey, and Tapscott, in press). We therefore
predicted that men would be more likely to use sexual coercion when there is a direct risk
of cuckoldry, and more likely to use sexual coaxing when the risk of cuckoldry is indirect.

Cuckoldry risk among partner rapists

Although using self-reported propensity for partner sexual coercion is useful for
quasi-experimental designs, evidence from men convicted of raping their romantic partner
addresses external validity of the cuckoldry risk hypothesis. The risk of infidelity has also
been implicated in these cases of domestic violence (reviewed in Buss, 2000), though few
have elucidated the etiological differences between men who physically assault their
partner and men who commit partner sexual assault (see Camilleri and Quinsey, 2009).
Following Daly and Wilson (1992), and Goetz and Shackelford (2006), we hypothesized
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that domestic assault functions as “coercive control” to prevent female infidelity, whereas
domestic sexual assault functions as a response to infidelity. Thus, we predicted that both
partner rapists and nonsexual partner assaulters would have experienced a number of
cuckoldry risk events prior to committing their offence, and that partner rapists would have
experienced more cuckoldry risk events prior to committing their offence than nonsexual
partner assaulters. More accurate categories would include infidelity certainty, suspected
infidelity, opportunity for infidelity, and no evidence of cuckoldry, but due to the small
sample size in the present study, there was not enough variability in these reports for an
accurate test. We therefore treated more types of cuckoldry risk events as indicating greater
risk of cuckoldry.

Predictions
In Study 1 we tested the predictions that men’s current propensity for partner sexual
coaxing would be related to recent and indirect cues to cuckoldry risk, that men’s current
propensity for partner sexual coercion would be related to recent and direct cues to
cuckoldry risk, and that no such relationships would be found among women. In Study 2
we tested the prediction that both partner rapists and partner assaulters experienced
cuckoldry risk events prior to their offence and that partner rapists experienced more of
these events.
STUDY 1: COMMUNITY SAMPLE
Methods
Participants
Of the 477 participants in this study, 370 participants were included in our analyses
because they met our eligibility criteria: were sexually active in a heterosexual relationship,
and provided usable responses (i.e., provided a value between 0 and 1.00 for the proportion
of time with partner since last having intercourse). Participants were recruited from both
the Psychology Department participant pool (nmales = 95, nfemales = 115) and the local
community (nmales = 79, nfemales = 81) to maximize the variability in age (min = 17 years,
max = 78 years, M = 27.8, SD = 14), relationship type (dating/not living together, n = 243;
marital/living together, n = 126), and relationship length (min < 1 year, max = 47 years, M
= 5.01, SD = 8.86).

Materials
Data for this study were collected using a survey format. This survey collected
information on (i) indirect and direct cuckoldry risk, (ii) propensity for sexual coercion and
sexual coaxing, and (iii) other demographic information. Two versions of the survey were
developed, tailoring questions and scales according to participant sex.

Indirect Cuckoldry Risk
Cuckoldry risk, sometimes referred to as sperm competition risk, was assayed
indirectly as the proportion of time with one’s partner since last having intercourse (PROP).
This was calculated by dividing the number of hours with one’s partner since last
intercourse by the number of hours since last intercourse. Another influential variable, the
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time since last having intercourse with one’s partner (TIME), has also been measured in
studies of sperm competition, but the reasons given for inclusion of this variable differed
between researchers. For example, Baker and Bellis (1993) treated TIME and PROP as
independent predictors, whereas Shackelford et al. (2002) treated TIME as a control.
Although the relationship between TIME and sperm competition is not well understood
(Shackelford et al., 2005), we argue that the relationship between PROP and any cuckoldry
risk criterion is moderated by TIME. That is, PROP should weaken as a predictor as the
time since having sex becomes more recent because having sex recently substantially
reduces any risk.

Direct Cuckoldry Risk
Whereas indirect measures of cuckoldry risk evaluate variability in the opportunity
for extra-pair copulations, direct measures of cuckoldry risk evaluates actual cues to
infidelity. To evaluate direct cuckoldry risk we adapted items from Shackelford and Buss’s
(1997) factor analysis on cues to infidelity. From a pool of 170 cues, they identified 65 cues
(e.g., she began avoiding talking about a certain other man in conversations with you) that
loaded onto 14 factors. A direct cuckoldry risk total score (DCRS-tot) was calculated by
summing the number of items answered in the affirmative. A higher score on the DCRS-tot
indicates higher cuckoldry risk. To approximate when these events occurred, the most
recent event for each factor was selected, then an average of those times were calculated
(DCRS-tim). In this case, a lower score indicates high cuckoldry risk because on average,
these events took place recently.

Sexual Coercion and Sexual Coaxing
Because we tested how sexual coercion varies over time, we could not use measures
of sexual coercion that includes historical items, such as the Sexual Coercion in Intimate
Relationships Scale (Shackelford and Goetz, 2004). The Tactics to Obtain Sex Scale
(TOSS; Camilleri, Quinsey, and Tapscott, in press) was used because it contains subscales
that measure current propensity for sexual coercion (COERCE) and sexual coaxing
(COAX). Participants rated 35 acts used to obtain sex from a reluctant sexual partner on a
5-point scale that ranges from definitely not to definitely in terms of the likelihood they
would use the act and how effective they think the act would be in obtaining sex if their
partner refused intercourse that evening. The COERCE subscale contains items such as
“physically restrain” and “slap or hit,” whereas the COAX subscale has items such as
“massage her/his neck or back” and “softly kiss her/his ears, neck, or face.” Scores for each
item were summed, then total scores for each subscale were calculated. The TOSS is
sensitive to proximal changes in interest for using such acts, COERCE correlates with
reported use of sexual coercion in relationships, and both subscales have excellent internal
reliability (Cronbach’s alphas > .89) and construct validity (Camilleri et al., in press).

Procedure
Participants visited our laboratory and provided informed consent prior to
completing the survey. Each participant completed the survey in a private room, and the
researcher was available throughout the session to answer any questions. Upon completion
of the survey, participants were debriefed.

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Data Management
We used multiple regression analyses to test several predictions so we followed
Cohen, Cohen, West, and Aiken’s (2003) data cleaning procedures for regression analyses.
Checking for leverage, discrepancy, and influence identified 13 outliers that were removed
from the data. Inclusion of these outliers weakened the effects but did not change the
interpretation of our results. A violation of the homoscedasticity assumption was corrected
by using a square root transformation on COERCE, and so all analyses with COERCE use
this transformation. All significant interactions were followed up using simple slopes
analyses (Aiken and West, 1991), which allowed us to interpret interactions between
continuous variables.
Results
Indirect Cuckoldry Risk
A significant main effect for TIME, F1,160 = 10.44, p = .001, and for PROP, F1,160 =
10.05, p = .002, on COAX are uninterpretable because of an interaction between TIME and
PROP, F1,160 = 8.38, p = .004. Observing the simple slopes (regressing COAX on PROP at
different levels of TIME, see Aiken and West, 1991) found that the less time spent with a
partner since last having intercourse, the greater the interest in using sexual coaxing but
only when the time since last having intercourse was moderate or long (see Figure 1).
Interestingly, when the time since last having intercourse was short, the relationship
between PROP and COAX was reversed. Neither TIME, PROP, nor the interaction
between them predicted COERCE, ps > .11. Consistent with our prediction, there were no
main effects or interactions among female participants, ps > .14.

Figure 1. Simple slopes of the relationship between PROP and COAX when the time since
last intercourse was high (+1 SD), moderate (mean), and low (-1 SD) (for graphing
procedures see Aiken and West, 1991; Cohen et al., 2003).





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Direct Cuckoldry Risk
There was a significant main effect for DCRS-tot on COERCE, F1,142 = 15.66, p <
.001 but not COAX, F1,142 = .30, p = .58. DCRS-tim did not predict COAX, F1,142 = 2.32, p
= .13, or COERCE, F1,142 = .24, p = .63. These results were also qualified by a significant
interaction between DCRS-tot and DCRS-tim on COERCE, F1,142 = 5.80, p = .02. Our
prediction was supported from a follow-up simple slopes analysis—there was a positive
relationship between the number of cuckoldry risk experiences and propensity for sexual
coercion only when these events took place more recently (see Figure 2). Apart from a
marginally significant relationship between DCRS-tot and COAX, F1,149 = 3.33, p = .07,
there were no significant main effects or interactions among female participants, ps > .12.

Figure 2. Simple slopes of the relationship between DCRS-tot and COERCE when the
average time since the risk events took place was long (+1 SD), moderate (mean), and
recent (-1 SD).


STUDY 2: FORENSIC SAMPLE
Methods
Offender sample
Archived files of 55 offenders who were either committed or assessed at a
maximum security psychiatric facility were reviewed. Files of nonsexual partner assaulters
(n = 30) were randomly selected, whereas all available partner rapist files were reviewed (n
= 25) due to their low base rate. Sample sizes varied across analyses due to data
availability.

Measures
To evaluate cuckoldry risk among convicted partner rapists and partner assaulters,
archived case files were reviewed by two raters for descriptions of the circumstances prior
to the offence. One rater was blind to study hypotheses. The degree to which offenders
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experienced cuckoldry risk events was tabulated by summing the number of risk event
types that preceded the assault. These events, selected because they are established cues to
infidelity (Shackelford and Buss, 1997; Shackelford et al., 2002), include: suspected,
known, or threatened infidelity; left/leaving partner for another man; experiencing jealousy;
sexual refusal or loss of sexual interest; separated or threatened separation; refused going
back to partner; or perpetrator reported a long period since last having intercourse with his
partner. Absence of cuckoldry risk events were coded only if crime synopsis information
was available and none of the risk items were applicable. The average percent agreement
across risk categories between the two raters was 91.2%.
Results
Partner rapists (M = 1.88, SD = .81) experienced significantly more cuckoldry risk
events prior to committing their offence than nonsexual partner assaulters (M = 1.28, SD =
.46), t23.25 = 2.61, p = .02 (adjusted for unequal variance).
Twenty-two of the 25 partner rapists had archived information about the crime. All
cuckoldry risk categories were experienced by these men: 27.2% suspected, knew, or were
threatened with infidelity; 9% had a partner who left or planned to leave for another man;
13.6% reported being jealous; 22.7% had a partner who refused or lost interest in sex;
40.9% were separated or threatened with separation; 18.2% had an ex-partner who did not
want to renew the relationship; and only 4.5% reported not having sexual intercourse with
their partner recently. When combining across cuckoldry risk items, a large proportion of
partner rapists experienced cuckoldry risk events (72.7%).
Twenty-nine of the 30 nonsexual partner assaulters had a crime synopsis in their
files. Of these men, 5 of the 7 cuckoldry risk categories were experienced: 31% suspected,
knew, or were threatened with infidelity; 6.9% had a partner who left or was leaving for
another man; 6.9% reported being jealous; 6.9% had a partner who refused or lost interest
in sex; 27.6% were separated or threatened with separation; and none of the partner
assaulters reported having an ex-partner who did not want to renew the relationship or did
not have sexual intercourse with his partner in a long time. When combining across
cuckoldry risk items, a large proportion of nonsexual partner assaulters experienced
cuckoldry risk events (62.1%). Though the difference between partner rapists and partner
assaulters in the proportion of men who experienced any cuckoldry risk event was in the
expected direction, the difference was not significant, Pearson ?2 = 0.14, p = 0.71.
Discussion
The purpose of these two studies was to provide a test of the partner sexual coercion
as a response to cuckoldry risk hypothesis by examining several important characteristics
of cuckoldry risk and the responses to such behavior. Each of these characteristics will be
described and we will conclude our discussion by addressing how partner sexual coercion
is related to other behaviors designed to manage cuckoldry risk.

Response to cuckoldry risk is not arbitrary
The strategy used to obtain sex from a reluctant sexual partner depends on the
available cues. Men were more likely to favor benign tactics when cues to cuckoldry risk
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were indirect—when men did not have sex in a while and spent a larger proportion of time
away from their partner, they were more likely to show an interest for sexual coaxing. On
the other hand, men who experienced more direct cues to infidelity reported a greater
propensity for sexual coercion when these cues occurred more recently. The facultative use
of these tactics makes sense when understanding the circumstances surrounding each type
of cue.
Indirect cues in the absence of direct cues do not mean one’s partner is interested in
other men, particularly if she is still sexually responsive. A female partner who refuses sex
under this scenario, however, may signal infidelity. Thus, sexual coaxing is a tactic that
would likely change a partner’s interest, and if disinterest is persistent there is still a low
enough risk where the cost of switching to sexual coercion outweighs the benefit
(especially if a coaxing strategy is successful each time). This strategy minimizes
cuckoldry risk while maintaining the benefit of retaining a mate. Alternatively, a greater
interest in coaxing may simply be a manifestation of another more common adaptation to
sperm competition—increasing sexual frequency (Shackelford, Goetz, Guta, and Schmitt,
2006). A male who has not maintained frequent copulations due to physical separation may
be more inclined to use sexual coaxing to “make up for lost time.”
On the other hand, experiencing recent cues to infidelity in addition to unrelenting
sexual disinterest is more diagnostic of imminent or recent infidelity. Women, for example,
report waiting 48 hours after an extra-pair copulation before resuming sexual activity with
their partner (Gallup et al., 2006). Under such circumstances, a coaxing strategy is likely a
futile one. More forceful tactics become less costly if they serve as a last-ditch effort to
copulate with a partner who is dissolving the relationship or has already left.
A greater interest in using tactics to obtain sex under cuckoldry risk conditions is
not arbitrary because they enhance the probability of successful fertilizations. Supporting
this view is the concept of last male sperm precedence (Birkhead, 2000), where males who
are last to copulate are most likely to achieve successful fertilization. Although last male
sperm precedence is typically found in bird and insect species, mating order effects have
been studied in mammals as well (Ginsberg and Huck, 1989). In humans, there is some
evidence that sperm displacement by males is a functional response to sperm competition
(Gallup et al., 2003; Goetz et al., 2005).

Cuckoldry risk is dynamic
Facultative mechanisms can either be developmentally fixed (i.e. tactic changes but
remains constant), or developmentally flexible (i.e. tactic switches over time). Our results
suggest the cuckoldry risk mechanism meets criteria for the latter. Both the proportion of
time with one’s partner and the number of cuckoldry risk incidents were related to interest
in obtaining sex only under certain temporal conditions. A strategy that maintains the same
coercive sexual strategy over long periods of time does not provide a selective advantage
due to the costs associated with such behavior, including victim injury, familial revenge,
and possible dissolution of the relationship. Though males may be willing to incur these
costs if the relationship is already on the brink of “breaking up,” switching back to a non-
coercive sexual strategy would minimize additional costs over the long term, whether it is
with the same partner or with any subsequent partners.
Satisfying our hypothesis, proportion was negatively related to interest in sexual
coaxing only when the time since last sex was further away. When testing predictions
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derived from the cuckoldry risk hypothesis, researchers are therefore advised to use a more
rigorous approach by measuring temporal moderators. There is a caveat, however, in
interpreting the PROP variable. In retrospect, it became apparent that having sex recently
not only negates any current risk but invalidates proportion as an index of risk. For
instance, spending 50% of the time with your partner since last having intercourse is
qualitatively different if coitus occurred 2 hours ago versus 2 weeks ago. The indirect risk
of cuckoldry is higher in the latter than in the former scenario. The positive relationship
between proportion and coaxing when time since sex is recent is therefore difficult to
explain because proportion is no longer meaningful.
From a practical perspective, cuckoldry risk is relevant to the dynamic risk
assessment literature (see Quinsey, Jones, Book, and Barr, 2006). Assessing the risk of
committing a violent or sexual offence has been used for tailoring treatment programs,
aiding front line workers, and informing judicial decisions. Because sexual coercion in
relationships appears to be a facultative response to cuckoldry risk, researchers and
practitioners interested in predicting the proximal risk of sexual coercion in relationships
should either test for the inclusion of cuckoldry risk when developing an actuarial tool or
include a measure of cuckoldry risk to complement other risk measures.

Coercive response to infidelity is sex-specific
Though sex differences in the frequency of partner sexual coercion are known,
understanding the sex-specific mechanism underlying these differences is not. By
demonstrating that men exhibit a greater interest for coercive strategies when more cues to
infidelity are experienced is consistent with the hypothesis that sexual coercion is a male
adaptation to cuckoldry risk and identifies one mechanism that accounts for these
differences. This finding is unique because predictors of violent and sexual behavior tend to
be the same between men and women (e.g., Harris, Rice, and Camilleri, 2004; Simourd and
Andrews, 1994). In these cases, sex differences can be accounted for in two ways: men
either have greater exposure to such risk factors, or men are more vulnerable to risk factors
than women (e.g., Cloninger’s two-threshold model; Cloninger, Reich, and Guze, 1975;
Cloninger, Christiansen, Reich, and Gottesman, 1978). Data from our study provides a
straightforward explanation because variability in sexual coercion is explained by a
sensitivity to cuckoldry risk only among men and not among women. That is—even if men
and women experience equal risks of infidelity, higher prevalence of sexual coercion
results from this male-specific response. Our data do not suggest women are uninterested in
sexual coaxing or coercion, but that their interest in such behavior is unrelated to temporal
changes in infidelity risk. An extension of our findings is to isolate male-specific cognitive,
neurological, and hormonal mechanisms involved with sexual arousal and proclivity for-,
or disinhibition to violence that operates during cuckoldry risk conditions.

Limitations of self-reports
Our first study measured self-reported propensity for sexual coaxing and coercion.
We fully acknowledge that using self-report propensity to assay sexual coercion does not
necessarily predict overt behavior. However, by using a self-report propensity measure we
were able to look at the relationship between theoretically relevant constructs that are
difficult to obtain in large numbers from convicted partner rapists. If behavior varies
according to fluctuations in cuckoldry risk, we expect a male psychology that supports
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