Human Factors relating to capacity for immediate cessation of sex following revoked consent.
Dr Anton Crabtree* MBBS FANZCA ACCAM.
Lecturer in Human Factors and Aviation Medicine.
Introduction
This paper gives an overview of issues in sexual assault cases involving initial consent and the subsequent withdrawal of consent from a scientific viewpoint and Human Factors and Ergonomics (HFE) analysis.
Background
A 2017 article by Theodore Bennett "Consent Interruptus: Rape Law and Cases of Initial Consent” (1) analyses legal issues in cases of initial (then withdrawn) consent i.e. cases where sex begins with initial consent and then “continues” despite consent being withdrawn. The article indicates that applying existing sexual assault laws in these cases can be problematic and may result in unjust outcomes.
Bennett noted changes to sexual assault laws in most jurisdictions in Australia meant that “…penetration is a continuing act (which only ends with withdrawal)” and the “introduction of the continuation provisions now means that consent is relevant at all stages of sex and to continue sex without consent can indeed constitute rape.” (1)
Bennett argues:
” …despite modern statutory reforms the application of the law in such cases is still plagued by several substantial legal difficulties, including the unclear meaning of ‘continue’ in statutory provisions and the uncertain legal standards set for the communication of non-consent.”(1)
The Australian Institute of Family Studies states that:
“Little research specifically examines the role of forensic medical evidence in sexual assault trial settings. Given current debates about the interface between law and science, and ongoing debate about improving criminal justice outcomes for sexual assault matters, particularly where consent is the contested issue, this is a significant gap.” (2)
HFE is an area of multidisciplinary scientific study – the study of how humans behave and interact with each other, taking account individual and interpersonal differences in human performance and limitations in an environmental context. This could help fill this evidential gap.
The study of HFE has achieved positive outcomes in other areas of human endeavour e.g. improving safety in aviation. The author believes it would be highly beneficial to recognise and implement the important scientific findings coming out of HFE studies in developing sexual assault policy and laws and in adjudicating sexual assault cases, including in cases involving withdrawal of consent.
This paper:
Revoked consent and HFE
This is a summary of some of the available science relating to HFE which may have relevance to revoked consent:
Communication
Communication is an exchange of facts, ideas, opinions, or emotions by two or more persons for mutual understanding. It can be verbal: written or spoken. Or non-verbal: tactile, visual or a combination (looking at someone while they speak). Written messages can be verified, spoken messages mostly cannot.
There are many aspects to effective communication, namely the sender, the message, the medium, the receiver, the perception, the interpretation, the decision, the action, and the feedback. If this process has been achieved it is known as “closed loop communication”.
Other important influences are the environment and the context. Sending a message or instruction of itself does not constitute communication. Communication cannot be assumed to have occurred unless the sender has taken steps to verify the message has been received and understood or has good reason to believe so. (We do this day to day, e.g. sending and receiving confirmation of SMS.)
Even relatively minor errors in communication, particularly where there is ambiguity of meaning, can have catastrophic outcomes as shown in the KLM and Pan Am 747’s Teneriffe Airport crashes which lead to 583 deaths.
This is why aviation has adopted a system of words and phrases that can only have one specific mutually understood meaning (for example, “hold short of” a specific location rather than “stop”). Other areas of human endeavour are also implementing standards, rules or laws governing communication particularly where it involves safety critical and time sensitive information. In addition, a requirement for readback is needed so that the message is clearly received and understood by all parties.
It is argued that the same should apply to laws governing sexual intercourse and affirmative consent. In Australian (and many other) jurisdictions there is now a legal requirement for affirmative consent – an example of closed loop communication. However, once consent is obtained there are no requirements that withdrawal of consent should be clearly communicated. This omission is a notable failure in our current legal system.
Sensory inattention
Sensory inattention is a neurocognitive process whereby the perception of sensory cues, stimuli or communication are involuntarily (or sometimes voluntarily) blocked. It is a normal human response and sometimes advantageous, such as in situations where there is need to focus or fixate on other tasks e.g. rushing into a burning building to save one’s child, or during a battle. It can manifest as inattentional deafness (Auditory Task Irrelevance) (4)(5) and Inattentional blindness, a type of 'sighted blindness' leading to an inability to perceive relevant environmental stimuli. (6) A common example is people focused on mobile phones while walking or playing video games.
Sensory inattention occurs particularly in situations of high arousal e.g. during the plateau and orgasmic phases of sexual intercourse. Sensory inattention is one of several HFE causes which explain why it is possible for one sexual partner to have a reasonable belief that consent to sexual intercourse still exists even after it has been withdrawn.
Startle / Surprise response.
The startle reflex has been described in research for over 100 years. It describes the response of a person to a sudden sharp unexpected stimulus. It has two components, a fast, involuntary reaction known as the “fright, fight, flight or freeze response.” This is followed by a much slower “cognitive assessment and decision-making process”. (7)
The surprise response is like the startle response however the surprise response can occur with a lesser unexpected stimulus or the absence of an expected stimulus.
There can be a persistent state of poor cognitive function, particularly if the stimulus is ambiguous. (7) Both Startle and Surprise can lead to a period of impaired information processing and cognitive function with poor decision making. It can even lead to a self-generating response, sometimes of prolonged duration, which involves the inability to correctly assess and correct the situation (for example, a pilot was cognitively impaired for nearly 3 minutes in the case of the Air France 447 disaster. Miscommunication between the pilots exacerbated the situation). (8)
There are several variables that will impact upon this response, including high levels of arousal, individual differences, inexperience, unpreparedness, illness and others. There have been recent comprehensive studies that have considerably improved our understanding of these normal phenomena (these studies have mostly come out of investigations into pilot response during flight incidents e.g. Air France flight 447, US Airways Flight 1549 aka “The Miracle in the Hudson”). (9)
Findings into the startle reflex could inform sexual assault cases by showing that it may not be possible to instantaneously respond to unexpected signals or communications indicating that consent has been withdrawn (i.e. just as there are claims that rape victims freeze in response to rape, it may be possible that sexual participants have a “freeze” response in reaction to a drastic change in circumstances i.e. withdrawal of consent).
Stimulus response time (SRT) / Perception response time (PRT)
Put simply, SRT is the time from when a stimulus can be sensed, to when the correct action is initiated. PRT is different in that it requires that the stimulus be perceived (recognised). SRT is variable but it cannot be instantaneous. For example, the SRT from an unambiguous stimulus such as a brake light to moving the foot from the accelerator to putting pressure on the brake pedal is upwards of 2.5. seconds. This is under good test conditions with normally alert experienced drivers. (10)
A stimulus cannot be acted upon unless it is perceived. A stimulus may need to be repeated, increased in intensity and/or it may require a different medium (sound, sight, touch) to be perceived. Similarly, in these sexual situations there will be a difference in SRT, when the man first receives the stimulus that consent is revoked, and PRT, when he perceived or realises that this is the message his partner is conveying.
Automatism and Automaticity
Both these terms describe actions processes that are unintentional. Automatism, involves actions that cannot be and are not consciously controlled. Examples include breathing during sleep, and parasomnias such as sleepwalking and sleep sex (or so called sexsomnia).
Automaticity describes involuntary actions that, when conscious, can be controlled if needed e.g. walking or breathing, as well as some actions which can only be voluntarily controlled up to a point e.g. breath holding, orgasm and ejaculation.
Sexsomnia has been accepted as a defence in cases of sexual intercourse without consent. It was ruled as automatism in Australia. (3) In Canada it has been ruled to be a mental disorder (R v Luedecke). Though extreme cases are rare, it appears that there is a range of sexual activity (sometimes mutual) that can occur during different stages of sleep, with the participants having no memory upon awakening. This could result in a person commencing or participating in sexual activity during sleep but not been aware of it upon awakening, and thus claiming it to be non-consensual.
Sexual intercourse is typically a combination of both the voluntary and involuntary. As arousal increases so do involuntary actions to the point pre-orgasm, involuntary thrusting and muscle contraction occur as well as profound sensory inattention. That means at some point, even if consent is revoked, sexual climax will still be inevitable.
Human factors in combination
It is common to have a combination of these factors in play simultaneously or sequentially. Level of experience is important. For example, inexperienced drivers are far more likely to be vulnerable to miscommunication, sensory inattention, startle / surprise response confusion and delayed stimulus response times – which is why learner drivers are required to have 120 hours directly supervised instruction.
Similar issues are relevant to sexual participants, especially those who have little or no experience or knowledge.
Case law examples
This paper will now consider some of the well-known cases involving revoked consent in the context of HFE science.
Ibbs v The Queen [1988] WAR 91; see also Ibbs v the Queen [2001] WASCA 129.
The earliest Australian case to deal with revoked consent involved Perth man, Kevin Ibbs, who became known as the “30-second rapist”.
The facts were unusual, but essentially were that Ibbs and his neighbour (a friend of his wife) had consensual sex together at his home – an event planned by Ibbs’ wife who apparently wished to get rid of her husband. The neighbour accused Ibbs of rape, claiming that Ibbs continued to have sex with her for a time after she had withdrawn consent by complaining that the encounter was “not right” and trying to push Ibbs away. The trial judge noted in the sentencing remarks that:
“Your criminal responsibility results from the continuation of penetration either after she had withdrawn her consent or after any mistake on your part had ceased to be honest and reasonable. On the evidence I find it difficult to identify the period of the continuation after the critical moment. It is however enough to say that it was an appreciable time, perhaps up to 30 seconds after she commenced to try to push you away from her.”
It is arguable from a HFE standpoint that the messaging from the complainant prior to the point of the push was unclear and ambiguous - she protested it was “not right” because Ibbs’ wife was her best friend. Also, even at the time of the push, the withdrawal of consent was likely to have been entirely unexpected (particularly because Ibbs had stopped previously at the complainant’s request and asked her to confirm with his wife that she was OK with the sexual encounter). This means it is likely Ibbs would have had a surprise response that would delay comprehension and formulation of the correct action. Even his response “it won’t be long” does not indicate that the withdrawal of consent had been properly interpreted (it is not clear from the facts of the case whether Ibbs admitted he had understood consent had been withdrawn at the time of the push).
Despite this, both the trial judge and the Court of Appeal (which dismissed Ibbs’ appeal) indicated in their judgements that Ibbs’ response to the push should have been an instantaneous (or near instantaneous) withdrawal. In the author’s view, this position does not take HFE science into account. Allowing for factors such as Stimulus Response Time, Miscommunication Startle / Surprise response it is entirely plausible that Ibbs could go for a further 30 seconds lacking the perception or reasonable belief that consent had been withdrawn.
A sad side note to this case is that, although Ibbs was eventually acquitted after the complainant and his (then ex) wife admitted to setting the rape allegation up, he committed suicide in September 2008 at the age of 56.
2. The blind man and underaged assailants.
R v Morton (1998) 143 FLR 268, 270.
R v Morton involved a blind man who was set upon by three young girls, who pulled down his pants and a five-year-old then commenced fellatio he claimed without his consent. As the judge commented: “It seems clear that the initial introduction of the accused’s penis into her mouth did not occur as the result of any voluntary act on his part”.
However, Morton was convicted based on “voluntarily” allowing the act to continue by not moving, i.e. rape by omission. It was not contested that this was only “for a few seconds”. Morton did not take immediate steps to remove his penis from the child’s mouth. The encounter ended when the child withdrew. Morton testified that he did not react immediately because he tended to freeze in response to unexpected events due to his impaired vision. This evidence was supported by other witnesses who testified of his propensity to freeze. In these circumstances, feeling a small mouth and sharp teeth around his penis would be a genuinely startling event and freezing is a normal non-volitional reaction to startle.
Additionally, even when he had recovered sufficiently to make a neurocognitive assessment, he would be justified in his fear of his penis being bitten if he reacted in any other way than freezing. It is noted that the trial judge did not accept that Morton was afraid of being bitten due to a later incident where Morton had allowed the child to touch his penis in the bathroom.
Despite Morton’s “freezing” explanation for why he did not immediately take action to cease the encounter, Morton was convicted because “…the decisive issue… fell for determination in the context of facts which were largely undisputed”. That is, the evidence of a startle response and freezing appears not to have been considered relevant to the fact that Morton had technically engaged in sexual intercourse with a minor for at least a few seconds.
As noted above, it has long been accepted by the scientific community that it is not uncommon for rape victims to freeze and remain silent when assaulted. Why would we think different rules should apply for a male victim who has not voluntarily commenced any sexual activity?
A recent unpublished NSW sexual assault case demonstrates a typical startle/surprise reaction manifesting as a “freeze” response in this case of alleged revoked consent. This was exacerbated by unfavourable ergonomics, sensory overload and miscommunication.
After meeting through mutual friends, the complainant (16-year-old female) and the defendant, JP, (18-year-old male) commenced texting, including texts of a sexual nature. At one point, the complainant told police that the sexual texting had been a form of “trolling” or “bullying” by her against JP.
The incident which led to the sexual assault charge involved JP and the complainant getting into JP’s car and commencing sexual intercourse with mutual consent. She was on top of him, with him lying on his back in very confined space. At some point during intercourse when the complainant was on top of JP, the complainant revoked consent. There was some uncertainty in the evidence about the length of the intercourse, however the trial documents indicate the complainant said “no” about halfway through the coitus.
JP acknowledged that the complainant had said no, but as she was on top, he could not withdraw. From an ergonomic point of view, it’s unlikely he would have had the strength or room to lift the complainant off him in order to extract his penis. He also indicated to others that he did not want to “grab” the complainant to try to move her as he was worried about her taking it as assault.
In a call following the encounter, he said to the complainant, “I will admit that I did freeze. I did not intend to use you, I did not plan for that, I’m sorry that it happened, I froze and we continued” and “I basically lost control, went into a lost mind”.
All these statements are consistent with a normal response to an unexpected and unprecedented set of circumstances. The defendant talks about the fact that he “froze” and his “lost mind” – a description consistent with “sensory overload” described by a Queensland Government health publication as follows: "Sensory overload is when your five senses—light, sound, taste, touch, and smell—take in more information that your brain can process. Overwhelmed by all the input, the brain responds as it would to a life-threatening situation and enters fight, flight, or freeze mode”.
Due to the limitations of Human Information Processing, correct neurocognitive assessment could not occur until sometime after the event (perhaps half an hour, but often up to days later.) He was not in a position to properly process the revoked consent and react with immediate withdrawal.
Despite serious credibility issues with the complainant, the prosecution commenced proceedings against the defendant. However, the jury acquitted the defendant.
Observations on the cases
What these three cases have in common, from a human factors viewpoint, are the common phenomena of miscommunication, surprise/startle response and sensory inattention (inattentional deafness). It is extraordinary that these critical factors are being ignored in current case law regarding male response to revoked consent.
In Australia it appears that the law assumes that men can instantaneously respond to even ambiguous communication of revoked consent, without any regard to neurocognitive and physiological limitations. Bennett speaks approvingly of this position and argues that, “The notion that law should allow a reasonable time to withdraw in cases of initial consent is thoroughly problematic”. This is because, Bennett claims, it perpetuates a rape myth of the unstoppable male, unable to control himself during sex. For Bennett, this is undesirable. Whilst issues of moral self-control are relevant to this discussion, what is conspicuously absent is an appreciation of the science relevant to this question rather than broad espousal of “desirable” social mores.
The notion that a person is capable of immediate cessation of sexual activity on withdrawal of consent is also arguably thoroughly problematic considering the relevant scientific findings. Bennett also notes the problems with immediate cessation, noting that, “Whilst an allowance for reasonable time to withdraw may be flawed because it under-values a person’s general self-control during sex, a requirement for immediate withdrawal may be flawed for over-valuing a person’s self-control at each and every stage of sex”.
At high levels of sexual arousal, males are subject to sensory overload, where their psychological/physical resources are focused on their growing excitement. This means it may take very clear, repeated and even forceful intervention for the male to perceive consent is being revoked. It is unrealistic to assume a man at such a time is in full control of his neurocognitive processes, and physical responses. It is unrealistic to expect that cessation of the sexual act and withdrawal of the penis can occur instantaneously or near instantaneously at the time a complainant decides to revoke consent. It is the author’s view, given the serious consequences for defendants that there should be a requirement on complainants (in cases where initial consent has been given) to have ensured that withdrawal of consent is understood, even if this requires clear repeated and escalating intense words and actions.
In summary:
The criminalisation of normal male sexual response
In HFE and safety science it is established that an approach to improving safety that relies purely upon findings of blame, negligence, civil and criminal liability, and increasingly severe sanctions reaches a point of diminishing returns. This process inevitably becomes counterproductive, and unjust. (12,13,14)
Numerous government bodies have increasingly endorsed these principles (e.g. NSW Clinical Excellence Commission, Queensland Government). (15,16)
There is evidence that the sexual assault prosecution process in Australia is becoming unjust. NSW District Court Judge Robert Newlinds was scathing in his condemnation of the NSW DPP in bringing a number of baseless rape complaints to trial. In one case a young man spent 8 months in jail on remand despite the fact that that the sex was “clearly consensual”. Going further Judge Newlinds accused the DPP of abrogating their responsibility in failing to properly investigate the flawed evidence and to properly interrogate the complainant. (17)
These concerns are not unique to Australian jurisdictions, as well summarized by Professor Meridith Duncan, University of Houston).
“However well-intentioned these modifications have been, rape law provisions in some jurisdictions are much too broad and risk resulting in rape convictions of non-deserving individuals”. (18)
The benefit of proper HFE investigations is well proven in other fields. The Aviation industry has the best model and proven outcome because Cockpit Voice Recorders and Flight Data Recorders allow a unique insight into the fallibility of even the best trained pilots, showing that as humans, we are all prone to the consequences of miscommunications, sensory inattention/overload, startle/surprise.
What HFE science can bring to the table is a framework of how to better formulate sexual assault laws and policy and investigations and prosecutions of sexual assault cases, especially in withdrawn consent cases. Properly understood and applied, this science could help explain situations where the complainant believes consent has been revoked, but the accused genuinely believes that it has not.
The most important proven principle of human of HFE investigations is not to jump to conclusion, particularly of blame or culpability. HFE demonstrates that an approach that combines sound investigative process and proper support for victims/complainants can co-exist with the presumption of innocence and the right to due process. The science has shown us that this approach combined with better understanding and education leads to better outcomes.
It is all the more important that we closely examine the impact of sexual assault law changes on the rights of the accused to a fair trial. Just as it is unfair to rape victims to not appreciate the neuroscience behind responses to sexual assault, it is also unfair to introduce enthusiastic/affirmative consent laws with no proper consideration or understanding of the cognitive capacity of a sexual participant to respond immediately to revoked consent.
The absence of the rigorous assessment and well-established scientific considerations of Human Factors analysis is a glaring omission to any claim of a fair system of justice for persons accused of sexual assault after revoked consent. Ignoring the science inevitably risks further miscarriage of justice which can be catastrophic to individuals and families and damaging to society.
References
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https://www.ntsb.gov/investigations/accidentreports/reports/aar1003.pdf
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12. To Err is Human Building a Safer Health System Institute of Medicine Institute of Medicine (US) Committee on Quality of Health Care in America
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13. James Reason, “Human Error”
14. Sidney Dekker” Just Culture”
17. Natasha Robinson, The Australian newspaper Legal affairs December 15, 2023
18. Meredith J Duncan, ‘Sex Crimes and Sexual Miscues: The Need for a Clearer Line Between Forcible Rape and Non-consensual Sex’ (2007) 42 Wake Forest Law Review 1087, 1117”
*The author’s name has been disguised to protect their identity because of the tricky ideological climate in today’s academic world.