Crime and weather, weather and crime

It feels like winter here has finally passed. Yes its May. Yes its Memorial Day weekend. Yes I live in Wisconsin. And yes, the day's high and low were a 20 degree (F) difference. Yes it snowed recently in Colorado. There's even a recent report from our own government regarding climate change.

A very kind person wrote me a bit ago (please feel free, you're more than welcome) and suggested this topic. The temperature swing and the fact that the season finally changed got me thinking. Is there a connection between weather and crime rates? I'll share my hypothesis, read, and return.

Does crime go down with unfavorable weather? I'll venture an indirect yes, but it's not like inclement weather will stop my car from being stolen. My guess is that horrid weather will stop a person from going out, in general. Get that day down to 25 below zero with a windchill to -40 F and my guess is THAT would make the local car thief think twice. Oh, not about my car, but about their welfare. Will the destructive winds having fun with aluminum siding kites make my car any more lock proof? Nope. The only thing weather does (as far as "my" day's plans goes) is affects my decision to go through with them. Am I an expert in any of this? Not in the least.

My findings

It seems weather temperature does have an effect. Cold seems to bring it down, while warmer temperatures opposite. For example, in a Feb. 2014 report from the Lafourche-Terrebonne News (Louisiana): 

“Law enforcement agencies do experience a decrease in crimes due to cold weather,” Thibodaux Police spokesman David Melancon said. “I don’t have any exact numbers, but traditionally when the weather is bad, people go inside. Criminals are people, too, so they tend to stay inside as well.”
“Crime doesn’t come to a halt during cold weather, but it does slow down,” Terrebonne Parish Sheriff Jerry Larpenter said. “Thieves, their hands get cold, and they’re scared of falling into cold water, so they tend to stay home.”
Though freezing temperatures may have discouraged certain illegal activity, officials said crimes involving drugs are just as likely to happen during cold weather as they are any other time.
“If you’re a drug addict, you’re still going to go find your drugs. If you’re a drug dealer, you’re still going to sell your drugs,” Larpenter said. “The cold isn’t going to stop them.”

I got a kick out of that last bit, if you're a drug dealer ... the cold isn't going to stop you.

Back in March 2012, Chicago Magazine covered this relationship. Their article suggests that in warmer seasons more people go outside more. Er-go, more opportunities. The probability analysis just makes sense. "More social interactions increases the chances for violence." They refer this to the Routine Activities Theory and point to a Wired article from 2011. Funny though, you'd think nicer weather would put people in a better mood.

Ok, so we have a couple pieces aiming towards telling us that - in a simplistic way - nice days send us outside, bad days keep us holed away. Want another? This past April a local Chicago CBS news station reported that "[Chicago's] first-quarter murder total this year hit its lowest number since 1958". Was it that Chicago's law enforcement were rocking it? Was it that the northern Midwest's winter was really oppressive? Some combination of both?

The Windy City wasn't the only one to see lower crime rates. This April report from Camden, PA, calls its town (let's see if I can get this right here) “America’s Most Dangerous City.” It says total crime decreased about 30 percent comparing first quarter '14 to '13. Was it that the new county police department was rocking it? Was it that the northern Eastern coast's winter was really oppressive? Some combination of both? 

Here: "“I don’t think the weather has affected the number of murders in Philadelphia this year,” said Camden County Freeholder Director Lou Cappelli. According to the Philadelphia Police Department, the number of homicides in the city rose 13 percent during the same time frame, and aggravated assaults with a gun slipped 6 percent." Comparing winter to another, crime went down was lower.

So where are we at with this? Temperature CAN have an affect? (Not necessarily will.) Wired says heat CAN makes things worse ... but only to a point? I need more. I need help. I need ... Harvard.

One study from Harvard John F. Kennedy School of Government's starts using the word "prevent" when talking about weather and crime. Specifically this summary explains that while a heat wave can influence a crime wave and conversely a cold snap can influence a peace wave (Did I just make "peace wave" up?), the time period after the strange weather shows the reverse in crime. The 2005 study's co-author Kennedy School assistant professor Brian Jacob sets it straight, “crime delayed is not necessarily crime prevented.”

Take a moment and soak in that statement.

(The following link connects to a rather large PDF file, i.e. the study itself. The cover page states that it should be downloaded for personal use only.) Another Harvard study from May 2012, the working paper "Crime, Weather, and Climate Change" by Matthew Ranson, tries to see if weather does have an effect on crime in a long-term scale. More-over, does weather have a LASTING effect on crime rates? Just because today might be too cold to crime doesn't mean tomorrow will be, right?

Ranson drops a bomb and just comes out and says what we all are thinking: there is insufficient evidence that weather has a lasting effect on crime. Later he extrapolates that if climate change continues, weather will have a stronger connection with crime rates for far into the future.

I leave you with what I used to think a seemingly absurd question. As the polar glaciers melt, what are the chances of my car being broken into?

Thank you and stay safe out there.