Cold facts and hot blood
I doubt you had your bike nicked this week. But your car? That's a different story.
Most crime is seasonal and, as we shiver in the current cold snap, the warming news is that a wide variety of criminal behaviour goes down with the mercury.
But this is no time to relax. January turns out to be the peak month for theft of a motor vehicle, robbery of a business property and domestic burglary.
I was prompted to investigate the links between crime and the seasons following this week's report from the UK Statistics Authority [pdf] which highlighted the dangers in comparing criminal activity in June with that in October.
Research done for the Home Office a couple of years ago [pdf] investigated the level of 29 crime types, month by month over a decade. All but four of those they looked at showed seasonal patterns.
Most violent crime goes up in the summer and down in the winter. Wounding, rape, assault and conspiracy to murder all show significantly higher rates between May and August. Arson is a crime for mid-summer, with July and August the months for deliberate fire-setting.
The clearest seasonal pattern is attached to "theft of a pedal cycle" - 28.9% above average in September and 31.3% below the norm in February.
Non-domestic burglary appears to be particularly fashionable in the late spring while the domestic burglar prefers the winter months. January is 11% above trend, although the researchers wonder whether this is because people are away at Christmas and only discover the break-in on their return after New Year.
Another theory is that burglars have a break at Christmas too, and then "over-compensate in January". Or it might be that there is more to steal and more need to burgle after the excesses of the holidays.
Perhaps the thought of a nice warm car on a cold day is why motor vehicle theft is 6.3% up in January and a similar amount in March but down more than 6% from June until August.
A few crimes show regular peaks and troughs each year but not related to the seasons.
This may be because the research is based on recorded crime figures which can reflect police activity rather than actual crime, for example dangerous driving campaigns. In some cases, the researchers suggest that differences may simply reflect the fact that some months are longer than others.
The link between temperature and violence has long been accepted.
"Did you know, Putnam, that more murders are committed at 92 Fahrenheit than any other temperature? I read an article once. Lower temperatures, people are easygoing. Over 92, it's too hot to move. But just 92, people get irritable.
This extract from the film It Came From Outer Space, based on a Ray Bradbury short story, neatly sums up the theory. Academics have tried to demonstrate the point ever since, although the Home Office research finds weak correlation between the seasons and homicides. Not all criminologists agree, and the theories are many and varied.
Francesco Bruno from Rome's La Sapienza University says there is a physiological explanation for why there are more murders in Italy during hot weather. His figures show an average of two murders a day but rising to 2.3 in the warmest periods.
"The cerebral cortex needs a lot of water to function well," he claims. "When the temperature soars, it can be a struggle to control both our destructive and auto-destructive impulses, which arrive from the deepest parts of the brain, resulting in the tragedies we read in the newspapers''.
American research offers a similar explanation. "The human body generates adrenaline in response to excessive heat; adrenaline is helpful in keeping the body within safe limits, but we think that as a side effect it leads to aggression (which is often inappropriate)."
The idea that heat inspires violence is hardly a new one. The Belgian social statistician Adolphe Quetelet concluded in the 19th Century that people in hotter countries were more violent than those in colder nations.
And the theory has been taken further with contemporary researchers suggesting that a heatwave or heavy rain has a direct link to crime rates.
One US study [pdf] goes so far as to suggest that "a ten degree (F) increase in the average weekly temperature is correlated with about a 5% increase in criminal activity. Precipitation, on the other hand, is associated with reductions in criminal activity. An increase in average weekly precipitation of one inch is associated with a 10% reduction in violence".
All of which demonstrates why statisticians get so hot under the collar when politicians coolly spout month-on-month figures to convince us that crime is going up or down.
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I would've thought Bike theft went up and down with Cambridge university terms
all seems reasonably obvious - more physical violence in summer, when people are going out more
But keep on questioning the figures, Mark, especially government ones
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When it comes to bicycle thefts being much lower during the winter months I expect that is simply because there are far fewer bikes around anyway. Most people have them stored away because they don't like riding a bike in the cold or even the dark.
There is bound to be some seasonal effects on types of crime for a variety of different reasons.
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I once knew a retired beat bobby from the Dixon of Dock Green era who said that when it rained cats and dogs he`d go to the cinema for a few hours, because all the criminals would stay indoors.
It does seem logical that crimes that require either victims or perpetrators to travel outside rise in the warmer months.
Over summer people are more likely to walk around, visit each other or drink in pubs in the evenings (and youngsters are more likely to stay out in the evenings) hence the rise in wounding, rape, assault, arson and conspiracy to murder.
Likewise people may be tempted to cycle more in warmer weather, hence more opportunities for bikes to be stolen.
In winter people stay indoors as much as possible, they also try and save money following Christmas; the rise in burglaries in January may reflect burglars’ lack of post Christmas cash combined with the knowledge that `nearly new` items may be available.
Does warmer weather increase tendencies to be violent? It may be better to ask if cold reduces the likelihood of violence? The body uses more calories to maintain body heat and small changes in temperature causes reduced circulation to outer parts of the body. We`re less likely to do many things when we feel cold.
Perhaps the return of a comfortable ambient temperature (75 F/23 C) is all that is required; though hot, humid nights may result in less sleep and greater irritability.
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Excellent and fascinating article.
Of course, one might wonder why crime rates appear to be falling across the globe, given that we're told global warming is such a problem!
Obviously, it's about more than just the weather... and that's likely to be more the case for murders than the more common crimes.
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I suppose the idea that the chances of singling out a rape victim during a blizzard or nicking a bike when the roads are sheet ice is altogether too prosaic in an age where we want technical reasons everything:-)
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Went out tonight to nick a bike, nothing to be found. Nicked a car instead.
All very interesting, but not sure how it helps anything. But just think how much public sector time and effort has been spent putting these figure together.
And while the real coppers have been filling in the forms to collate the statistics, muppets like these are policing the streets.
http://www.youtube.com/watch?v=RKl2sEN4yNM
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Simple explanation for increase in car thefts in cold weather...
People leave their cars running to warm up while they chip ice off windows, run back inside house to get water for washer bottle etc. Villains find car theft hard work without keys (imobilisers compulsory on new cars for over 10 years) so a car running on a drive with the keys in it is a god send to them.
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If a bike is stolen from the locked shed in which it is stored is this classified as a burglary or a bike theft?
Also how many of the bikes were securely locked?
One thing I learned long ago was that chummy is not usually around in the morning. In the afternoon people begin to tire and get careless and, of course, night is always a good cover for nefarious activity. So he or she gets the benefit of a lie-in.
One thing I have also found when I have apprehended thieves during the course of my business - often employees - they always say that everyone else it at it as well as them so why are they being persecuted.
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Metropolitan Police - 0
Muslim Agitators - 1
All the above is beside the point if we are not going to uphold basic law and order!
On Saturday a huge crowd, comprised of muslims supported by Socialist Workers Party (Trotskyist) activists confronted a large body of police.
If it had been miners or any other ordinary British section of the community they would have been baton charged and brought back into order.
I have seen video footage of what actually happened, which must have been shot by an agitator on the front edge of the body of muslim rioters. The police were being taunted with shouts of "Run, cowards, run!". And they were running. And they kept on running. It was an utter disgrace! They allowed themselves to be routed by an unruly mob, without a single blow ever being struck. The muslims were right to call them cowards.
I keep hearing people saying that we are going to lose our country to these muslims in the end, and I have now seen how it is going to start to happen. This is the thin end of the wedge. God help us when the thick end arrives.
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Oh, yes. I forgot to mention in my previous post (probably too annoyed) that the thing that capped it all off was that neither the BBC nor anywhere else as far as I could see, was carrying any news footage of this near-riot by the muslims in London on Saturday. Am I to assume that the routing of a large body of police by a mob is not now considered a newsworthy event? It beggars belief!
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I'm amazing you haven't considered the obvious reason break-ins rise in the winter months - it's dark much more of the time.
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