Genes and sexual offending: a lawyer’s perspective

Tuesday, April 14th, 2015 | Colin Gavaghan | No Comments

The largest survey of its kind ever conducted has revealed a strong genetic component to sexual offending, which appears to hold a significant influence on the risk of close male relatives going on to commit a sex crime.

So proclaimed the article in last week’s NZ Herald. Reporting on research published in the International Journal of Epidemiology, the piece stressed that the researchers “said the findings should not be used to excuse sex offending, to restrict the freedom of the male relatives of sex offenders, or to suggest that there are genes for rape or paedophilia.”

These particular findings may justify none of those measures – as Emily Underwood explains, methodological limitations mean that we need to be careful of leaping to any such conclusions based on this study. But can we be confident that genetic evidence will never be able to fill any such roles?

In a recent publication (pre-review version here: Genetic defense article, web version) Amir Bastani and I explored the possibilities for a genetic-based defence (full or partial). In particular, we considered the possibility of a volitional defence, based on some impairment to the defendant’s ability to control his urges. (The article, I should say, isn’t really an argument for such a defence, so much as an argument against a certain kind of argument against it. If you can follow that…)

In the article, we take as a case study the MAOA gene. This has – somewhat controversially – been linked to certain forms of antisocial and criminal behaviour. Although the precise causal mechanism by which the gene variant affects behavior is not certain, various theories have been advanced as to how it might work, including by affecting levels of certain neurotransmitters like dopamine and serotonin, or the volume of certain brain structures like the amygdala.

The most credible claims about MAOA are that it has some bearing on crimes of what are sometimes called “hot” aggression – unplanned, impulsive actions that inevitably result in the offender being caught and punished, as opposed to premeditated crimes from which the offender hopes to gain. Though it is still far from certain, evidence is emerging that there may be a genetic component in our ability to exercise self restraint, control our temper, or resist our urges.

We all have urges all the time, but the law – and common morality – quite reasonably expects us to control them, and punishes us when we act on urges that involve criminality. The mere fact that someone had deviant or violent urges would not, in itself, provide a defence. Rather, the defence would only apply to those whose capacity for self-restraint is significantly impaired, such that they are rendered incapable of resisting those urges. It’s a central tenet of criminal law that we don’t punish people for that which they could not avoid. Hence, we might think, punishing people for genuinely uncontrollable behaviour is fundamentally unjust.

It may not be a major surprise to learn that this line of argument is not particularly popular, whether with politicians, the general public, or many academics. For one thing, it can sound like a mechanism for “getting away with” horrible crimes. It wasn’t me, Your Honour, my genes made me do it.

While any defence can be exploited by cynical opportunists, though, it isn’t clear why we should be more suspicious of volition-based defences than of, say, self-defence or the sort of insanity defence (“cognitive” insanity) that we currently allow. So why are volition-based defences not presently accepted in New Zealand, either in the form of a volitional limb to our insanity defence, or a diminished responsibility partial defence?

One of the suggested reasons for rejecting such defences is the claimed impossibility of distinguishing those who genuinely could not control their urges, from those who merely chose not to do so. It’s certainly true that a jury considering such a defence would be denied direct access to the mental state of the accused. This, however, is true of any of the mental states that concern the criminal law. As Lord Bridge said in one famous English murder case: ‘you cannot take the top of a man’s head off and look into his mind and actually see what his intent was at any given moment.’

Faced with this epistemic challenge, the law doesn’t simply abandon attempts to determine what was known, or understood, or intended by the accused. Rather, it sets about a process of inquiry that involves drawing inferences from external evidence – how the accused behaved, what he said, his background – and piecing together the most plausible account of his behaviour.

In the article, Amir and I considered a couple of examples of this kind of inferential thinking. Basically, the court is being asked: given all of the evidence, what is the most likely explanation for the defendant’s conduct? That may not sound like a particularly scientific process, but it can be informed to some extent by scientific evidence. And we see no reason why genetic evidence couldn’t be considered in the mix, long with psychiatric/psychological and all of the other sorts of evidence routinely heard in criminal trials. The judge or jury would be free to accept it or reject it – there’s no requirement to accept the defendant’s version of events at face value – but it would be on the table to be considered.

The Swedish study doesn’t seem to offer any suggested causal pathway by which any particular gene might influence offending. It doesn’t, for instance, claim that these offenders had impaired volitional capacities. It just notes that genetic relatives of offenders are themselves more likely to offend. That in itself wouldn’t be enough to make out a “genetic defence.” But the prospect of behavioural genetics informing the way we deal with criminals is not entirely the stuff of science fiction.

Of course, someone excused on the basis of volitional impairment wouldn’t necessarily just be set free to offend again. Just like those found not guilty by reason of insanity under the current rules, provisions would have to exist for detention and treatment of those who still pose a danger to the public. The very factor that means we shouldn’t blame them is also the very factor that might give us good reason to detain them in the interests of public safety.

Which brings me to the second potentially alarming possibility raised by the Swedish research. Is it possible that the presence of such a gene could provide the justification for, say, turning down parole applications, for preventive detention orders, or even – in the scenario that really worries fans of dystopian SF – for detaining people who haven’t committed any offence yet at all?

Again, the Swedish study offers little support for such a conclusion. The research found that close genetic relatives of sex offenders were 4 or 5 times more likely to commit a sex offence than unrelated men. But that still provides a likelihood of just 2.5%, which would presumably be far too low to justify any sort of preventive intervention. That this study doesn’t provide anything more than very weakly predictive, though, doesn’t preclude the possibility that such a thing will one day be discovered. Precisely what we would do with such information is really something worth thinking about.

Tackling the road toll (Part 2)

Thursday, March 12th, 2015 | Colin Gavaghan | No Comments

‘Real’ criminals, attribution errors, and a bit more blame-shifting

Some of the biases and assumptions around the key-grabbing phenomenon came to light during the debate around another initiative: the removal of the speeding discretion over the holiday period. The policy – which actually involved nothing more than enforcing the existing law – elicited a predictable backlash from the “motorist lobby”, as well as some of their populist political cheerleaders. [Warning: link is to WhaleOil blog. Caveat lector.]

The loudest of these voices was probably that of Ron Mark, NZ First’s police spokesperson, who had this to say: “I am genuinely concerned this focus is not just downright dangerous, it is making law abiding and safe drivers fearful of the Police.”

There were a few different elements to Mark’s position, but let’s puncture one myth first. If you’re driving at 110 km/h over the holiday period, then, unless you’re rushing a critically injured person to hospital or such like (see previous post re necessity), you are not a “law abiding driver”. You may be committing a crime that will typically not result in you being charged. But you are, nonetheless, committing a crime.

This sort of spurious distinction between “real” criminals and “decent hard working citizens” who just happen to break the law is common among populist politicians and “tough on crime” campaigners. It may be a form of Attribution Error – the process whereby we attribute mistakes or bad behavior by someone else to facts about their character or personality, whereas those we commit ourselves are readily attributed to circumstances. So while real criminal are just bad people, all those times I broke the law were required by the circumstances. That guy spinning his wheels is just a reckless hoon, whereas my overtaking on a blind corner is because I’m running late to pick up the kids, and anyway, this stretch of road is always quiet at this time.

A related strategy is the blame-shifting to “foreign drivers” of which we’ve heard so much recently. As pointed out on the excellent StatsChat blog, from the available evidence, “it looks as though foreign drivers are somewhat more dangerous, but that restricting them is very unlikely to prevent more than, say, 1-2% of crashes.”

Does it make sense to try to improve the safety record of tourist drivers, perhaps with initiatives like this? Very possibly. Does it make sense to focus most of our attention, or divert most of our resources in that direction? Almost certainly not. In fact, insofar as the scapegoating of Asian “foreign” drivers allows us to turn a blind eye to the problems with domestic driving, it may actually be worse than nothing.

But what politician has ever lost votes from telling the majority population that something isn’t their fault?

Keep your eyes on the road … and your mind as well

Ron Mark’s complaint about the holiday speed limit had another element to it, that also merits a bit of consideration.

People are saying to me that instead of driving to the conditions, their eyes are darting from the speedo to road and back again and that every time they see a Police car, they instinctively brake despite being well within the speed limit.

Is it possible that stricter policing will create perverse incentives for drivers to behave more dangerously?

From what I’ve been able to learn about this, I’d say the answer is: possible, but not likely. Of course, looking away from the road while the car is in motion is generally a bad idea, and distractions do indeed cause accidents. But not all distractions are equal. Glancing away from the road to check a traffic light, a rearview mirror or, yes, a speedometer may indeed lead to a net gain in safety.

In the case of the speedometer, the risk is likely to be at the low end of all the distractions drivers face. For one thing, glances at the speedo tend to be of very short duration: in his excellent book on driving behaviour, Tom Vanderbilt cites research showing that the average glance time to a speedo ranges between 0.65 and 0.8 seconds. That compares with just over one second to the mirror, and 1.27-1.4 seconds to the radio.

For another thing, speedometer readings are relatively cognitively undemanding. Experts in the psychology of driving have long realised that looking away from the road is only part of what causes accidents; a lot also depends on how much our mind is focused on it. Inattention matters as well as distraction. That’s why hands-free phones are still a problem. You can keep looking at the road while conversing with your spouse or client, but to paraphrase The Pixies, where is your mind?

The “cognitive load” imposed by a distraction can matter as well as – maybe as much as – the time it takes your eyes from the road. From that perspective, processing the information on a speedometer is likely to be less cognitively demanding than other in-car distractions; understanding a simple number requires less mental processing power than figuring out a map (digital or paper), or searching through the menu of an iPod.

My best guess, then, based on a half dozen hours of research, is that checks of a speedometer – which are both relatively brief and cognitively undemanding – are unlikely to detract very much from your “attention budget”, particularly when compared with other in-car systems like sat navs and music players, our outside distractions like roadside adverts or the stunning views on the Peninsula road. Some people share that view; others disagree. But here’s the thing. When we’re dealing with such high stakes, best guesses aren’t a good enough basis on which to form policy. There is actual research on this stuff, and people who spend time studying it. Unless Ron Marks has really looked into this subject, it’s pretty irresponsible to be spouting off about what works and what doesn’t. Because when it comes to road safety, good old common sense and gut instinct is often well wide of the mark.

Tackling the road toll (Part 1)

Thursday, March 12th, 2015 | Colin Gavaghan | 1 Comment

So, after a lengthy absence, and a few false starts, the L&ET blog is back. And I’m starting with a technology that isn’t so much emerging as long established, but with which law-makers and regulators are still really struggling to get to grips.

As I’ve confessed before on here, I’m that oddest of curiosities in New Zealand – a voluntary non-driver. Admitting this elicits a range of responses, from pity (is something wrong with him?) to puzzlement.

I do, however, spend a fair bit of time on the roads – as a passenger, a commuter, a pedestrian and a runner. So I think it’s safe to say that, even from a self-interested perspective, I share the concern of many NZers with improving our road safety record.

That record is indeed a pretty grim one. The death toll on NZ roads for 2012 (the last year for which comparative figures are available) was 6.9 per 100,000 people. That’s higher than Canada (5.8), Australia (5.2), Denmark (3), the UK (2.8), and placed us 24th out of the 29 nations assessed.

To express that in easier to imagine terms, that means between 250 and 300 violent, traumatic deaths every year. And a far higher tally of injuries, including paralysis, lost limbs and brain injuries.

It seems likely, then, that driving presents a far greater threat to most of us than, say, terrorism or released criminals. So it’s entirely right that our political representatives should be thinking about ways to make driving safer. In doing so, though, they face a problem. Well, a number of problems, really. Because there are few areas of everyday life that are so beset by logical fallacies, cognitive biases and flat-out prejudices than driving behaviour.

Since the commencement of the summer holiday period, we have seen an array of initiatives – from the official to the, shall we say, “improvised” – to improve road safety. On the one end of the spectrum, we have the range of “architectural” initiatives recently rolled out by the Government, including more directional arrows, rumble strips and signs. On the other extreme, we have the “vigilante” antics of the key confiscators. In the middle, we have the temporary removal by the NZ Police of the 10% “discretion” that usually sits atop the speed limit.

We probably all have our own intuitions about the extent to which these different initiatives are to be welcomed. Those initial intuitions, though, are likely to be strongly influenced by the sort of cognitive biases and untested assumptions that beset this area. If we are to make real progress with this problem, we need to find a way past those, to consider what really works. Once we’ve done that, another question arises, as to what price we’re willing to pay for those benefits.

Highway vigilantes, justified cannibals and horseback joyriders

The business of drivers “policing” the roads isn’t, of course, a policy initiative. How the authorities respond to it, however, does take us into the realm of law and policy. It seems pretty obvious that I commit a crime if I take away your car keys without a good reason, but what crime? In NZ law, “theft or stealing” involves “taking any property with intent to deprive any owner permanently of that property.” Which presumably wouldn’t be true in these cases.

The more promising option seems to be conversion of a vehicle or other conveyance. This was added to the Crimes Act in the mid-1990s to criminalise “joy-riders” – who, after all, don’t always intend to deprive permanently, so much as take the vehicle for a high-speed spin around town. It requires only that the offender “takes or uses for his or her own purposes or another person’s purposes (a) any vehicle, ship, or aircraft; or (b) any part of any vehicle, ship, or aircraft”. Or, um “any horse.” Subject to a very lawyerly reservation as to whether an ignition key is a “part” of a car, it seems likely that it could apply in the case of our vigilante key-snatchers too.

Would these antisocial justice warriors have a legal defence? Probably not. The old defence of Claim of Right for those who believe they’re acting lawfully might once have applied, but it was narrowed by the Crimes Amendment Act 2011, so that it now only applies where the taker believes s/he has a proprietary interest in the thing taken. As with the “joyriding” provision, this was introduced to fix a particular “problem” – in this case, the successful use of the defence by the Waihopai Three – but it almost certainly has potentially wider implications.

(One moral of this story, I think, is that the law is a blunt instrument. It’s very rarely possible to “fix” it in a super-specific way, and overspill is likely when we try.)

The only defence available to the key-snatchers would be necessity. That’s a rare and narrow escape route, that would involve showing that they were acting to prevent an imminent and non-trivial danger. Taking the keys from a mate who was dead drunk and intent on driving may be covered by this. Taking the keys from someone who you saw making a solitary mistake: not so much.

There are pretty good reasons why the law isn’t quick to allow claims that law-breaking was necessary. As Lord Coleridge famously put it in every law student’s favourite slice of gothic horror, necessity, ‘once admitted might be made the legal cloak for unbridled passion and atrocious crime.’ Had he been alive in 2015 NZ, he might well have added road rage, macho aggression and thinly veiled racism. It also seems likely that this particular example is likely to be one big proof of the Dunning-Kruger effect.

So that’s a thumbs down for the key snatchers – in all but the most extreme of circumstances. (Pro tip: the other guy being Chinese doesn’t qualify.)


Harming, wronging and looking online (part 1)

Thursday, October 23rd, 2014 | Colin Gavaghan | No Comments

Can someone be harmed or wronged by an act if they never know about it? Two news items over the past month have led me to revisit this old jurisprudential chestnut, albeit with a cyberlaw spin. The first arose in response to revelations that private, intimate pictures of the actress Jennifer Lawrence had been obtained by a hacker, and shared online.

As I’ve written before on this blog, I think that the unconsented sharing of intimate images is a serious matter, and one that merits a legal response. If it’s a crime to take an intimate picture without consent – as it currently is in New Zealand – then it’s my view that similar provisions should exist for sharing such images online. (An interesting question exists as to why privacy-violating pictures should elicit a criminal response at all, while equally privacy-violating writing, in the form of kiss-and-tell memoirs, is left with only to the civil law remedies of torts and injunctions. But that’s a question for another day.)

Less obvious, though, is what – if anything – the law ought to say about those who look at such pictures, but who play no active part in their production, acquisition or dissemination. For some commentators, those who do so are almost as bad as the original hacker. Feminist blogger Jessica Valenti put it this way: ‘When people seek out stolen images like the ones just released of Jennifer Lawrence, Kate Upton, and other celebrities, those people are violating these women in much the same way that the person who stole the pictures did.’

In a similar vein, Van Badham, writing in The Guardian, had this to say:

‘There are suggestions that prosecution may result not only for the hacker of the photos, but for those who view and share them. Good. To excuse viewing the images just because they’re available is deplorable. It’s the equivalent of creepily hiding in a wardrobe because a conversation may be taking place you’d be interested, excited or turned on to overhear.’

Leaving aside the fact that eavesdropping is not normally a criminal offence, does Badham have a point? Does Valenti?

Now for the second, more recent issue. If you use Facebook or Twitter, you’ll likely have read something over the past week or so about crime author John Grisham, whose – swiftly retracted – comments about child ‘pornography’ precipitated that most 21st century of responses, a TwitterStorm. In an interview, the main focus of which seems to have been the frankly insane imprisonment levels in the USA, Grisham referred to several categories of crime that he believed were punished too harshly. Among those was the viewing of ‘child pornography’.

Whatever merits there may have been to Grisham’s point probably weren’t much helped by the fact that his indignation seems to have been as much about the fact that ’60-year-old white men’ were being locked up, as about the jurisprudential questions. (It should be said that Grisham seems, in general, to be very aware of and concerned about the evidence of race-bias in American sentencing, so I’m inclined not to read too much into this. The Internet, of course, was less forgiving.) But is there anything to be said for his view?

The views expressed by Valenti and Badham on the one hand, and by Grisham on the other, represent pretty close to two opposite poles on a spectrum of answers to this question: what are we to make of people who view ‘abusive pictures.’ Precise figures aren’t available, but in the era of the Internet, it seems safe to say that this is a pretty substantial class of people. That being so, whether or not the law is responding to them in a suitable way is surely an important matter for consideration.

What is an ‘abusive picture’? The Jennifer Lawrence pictures obviously aren’t ‘abusive’ in the same way as the sorts of images to which Grisham is referring. Lawrence’s pictures were taken with her consent, something that obviously cannot be said of pictures of child abuse. Her pictures, rather, became ‘abusive’ at the point when they were hacked and shared. So the precise nature of the ‘wrong’ may be different as between the two cases. Additionally, we may doubt an equivalence in terms of likely harm; having one’s intimate pictures hacked and shared is likely to be pretty awful, but the suffering experienced by abused children is surely going to be of a different order altogether.

But there is a sense in which the two issues raise analogous questions, one of which relates to the role of the ‘passive observer’. Is it really true that someone who ‘merely’ looks at the Jennifer Lawrence pictures is ‘violating’ her? And is someone who ‘only’ looks at images of child abuse actually harming or wronging (for those may be two different questions) the children abused in its production? These questions in turn give rise to a further question, which is about what the law’s response should be. As I’ll hope to show, this isn’t a simple matter. It will depend in part on what the evidence around this category of offending shows, but it will depend as much on normative values – about what we think the law (both civil and criminal) ought to be setting out to achieve.

Based on some of the responses to Grisham’s comments, many people seem to regard even asking such questions as outrageous. Perhaps this is because the answers seem so obvious. I can understand that, up to a point. Whatever the rights and wrongs, I can see the appeal in looking at a beautiful, naked actress, but to the majority of us, the idea of looking at child pornography – to be blunt, pictures of children being abused – is viscerally repelant to an extent that drives out any semblance of empathy.  Less clear is whether the fact that something strikes most people as disgusting is a good enough reason to ban it. In other areas, liberals and progressives have tended to be skeptical of the ‘wisdom of repugnance.’ We don’t accept bans on homosexual acts just because (in some societies) most people find them disgusting. Generally, we demand a better justification for criminalisation, a justification couched in terms of harms and rights.

Whether such a justification can be found for ‘looking’ offences is precisely what I’m going to examine over the next couple of pieces. You may or may not agree with my answers. But hopefully, you’ll see the merit in asking the questions.

Cyber-bullying and the law

Thursday, February 27th, 2014 | Colin Gavaghan | 1 Comment

We have to assume it was a coincidence. The life of Charlotte Dawson, New Zealand’s most well-known victim of cyber-bullying, so happens to have ended on the same weekend as the consultation on New Zealand’s first cyber-bullying law. Continue reading

Through a Glass … legally? by Alex Franks

Friday, November 22nd, 2013 | Colin Gavaghan | No Comments

“Can I use Google Glass while driving?” is a frequently asked question on under the topic Google Glass. The answer Google gives is:

It depends on where you are and how you use it. 

As you probably know, most states have passed laws limiting the use of mobile devices while driving any motor vehicle, and most states post those rules on their department of motor vehicles websites. Read up and follow the law! Above all, even when you’re following the law, don’t hurt yourself or others by failing to pay attention to the road.

  Continue reading

‘Roast Busters’ are criminals – and we don’t need new laws to make them so

Wednesday, November 6th, 2013 | Colin Gavaghan | 1 Comment

  1. Something must be done.
  2. This is something.
  3. Therefore, we must do it.

Sir Humphrey’s famous Politician’s Syllogism seems to be alive and well in contemporary NZ politics. Certainly, Judith Collins’ tacking of the ‘cyber-bullying bill’ onto the coat-tails of the ‘Roast Busters’ debacle implies at least a smattering of Appleby logic. Continue reading

The gametic supermarket and accepting the unexpected

Sunday, October 6th, 2013 | Colin Gavaghan | No Comments

Over the weekend, I’ve been talking a bit to the media about this story – 23andMe’s patent of ‘a broad genetic analysis tool for allowing parents to select for specific traits in their offspring, such as lack of specific genetic diseases or eye colour.’ As Dov Fox explained, this ‘would enable prospective parents to handpick a sperm or egg donor with whom they would be likely to produce a child born with certain traits that they desire.’ Continue reading


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