One of the consistent and most fascinating facts that arises out of any serious study of psychology research is how much we are influenced by external factors.  So much of our behavior is influenced by seemingly small external factors.  We eat more when served bigger portions.  We spend more when sales are in effect.  Red cars are more likely to get speeding tickets.  We are more likely to marry someone who lives or works nearby.

But what about the truly profound and serious decisions of life?  What about something as serious as suicide?  Can it be that even such a grave decision is affected by seemingly small external factors?

The New York Times Magazine recently published a fascinating article “The Urge to End It All“, which addressed this very issue.  I highly recommend you read the entire article.

First, some numbers.  (I love numbers).  The current suicide rate is 11 victims per 100,000 people, the same as it was in 1965.  In 2005, about 32,000 Americans committed suicide, which is two times the numbers who were killed by homicide.

For many years the traditional view of suicide was that it reflects mental illness — depression, bipolar illness, psychosis, schizophrenia, or other mental illnesses.  This view assumed that the method of suicide was not important; it was the underlying mental illness that mattered.

But something happened in Britain in the 1960s and 1970s that set this model on its head.  It’s called the “British Coal Gas Story” and it goes like this:

For many years people in Britain heated their homes and stoves with coal gas.  This was very cheap, but the unburned gas had very high levels of carbon monoxide, and a leak or an opened valve could kill people in just a few minutes in a closed space.  This made it a popular method of suicide — “sticking one’s head in the oven” killed 2500 Britons a year by the late 1950s — half of all suicides in Britain!

Then the government phased out the use of coal gas, replacing it with natural gas, so that by the early 1970s almost no coal gas was used.  During this time Britain’s suicide rate dropped by a third, and has remained at that level since.

How can we understand this?  If suicide is the act of an ill mind, why didn’t those who could no longer use coal gas find another means? Why did the suicide rate in Britain drop by a third when the option of coal gas was no longer available?
The answer turns conventional wisdom about suicide on its head. Conventional wisdom is that people plan out suicides carefully, and so convenience of method shouldn’t matter. But actually it appears that often suicide is an impulsive act, and when you make it less convenient, people are less likely to complete the act.

Another example of this is found in the Golden Gate Bridge.  For years this gorgeous bridge has been a popular suicide point, where nearly 2000 people have ended their lives.  There have been many debates about erecting suicide barriers on the bridge, but most opponents say “they will just find another way.”

But Richard Seiden, professor at University of California Berkeley, collected data that addresses this issue.  What he did was to get a list of all potential jumpers who were stopped from committing suicide between 1937 in 1971, 515 people in all.  He then pulled their death certificate records to see how many had gone on to kill themselves later.  What would you guess was the percentage of these people who tried to jump off the Golden Gate Bridge and who later killed themselves?  50%?  75%?  25%?

Actually it was only 6%!  Even allowing that some accidents might have been suicides, the number only went up to 10%.  Although higher than the general population, it still means that for 90% of these would-be jumpers, they got past whatever was bothering them, and went on to live full lives.

Richard Seiden got some great stories out of this study.  One of the things he found was that would-be suicides tend to get very fixated on a particular method.  They tend to only have a Plan A, with no Plan B. As he says, “At the risk of stating the obvious,” Seiden said, “people who attempt suicide aren’t thinking clearly. They might have a Plan A, but there’s no Plan B. They get fixated. They don’t say, ‘Well, I can’t jump, so now I’m going to go shoot myself.”

One example he cites was a man who was grabbed on the east side of the bridge after pedestrians noticed him looking upset.  The problem was that he had picked out a spot on the west side of the bridge that he wanted to jump from, but there were six lanes of traffic between the two sides, and he was afraid of getting hit by a car on his way over!

As Seiden said, “Crazy, huh? But he recognized it.  When he told me the story, we both laughed about it.”

Another great example is from two bridges in Northwest Washington.  The Ellington Bridge and the Taft Bridge both span Rock Creek, and both have about a 125 foot drop into the gorge below.  For some reason the Ellington has always been famous as Washington’s “suicide bridge”.  About four people on average jumped from the Ellington Bridge each year as compared to slightly less than two people from the Taft.

In 1985, after a rash of suicides from the Ellington, a suicide barrier was erected on the Ellington Bridge, but not the Taft Bridge.  Opponents countered with the same argument, that if stopped from jumping from the Ellington, people would simply jump from the Taft.

But they were wrong.  Five years after the Ellington suicide barrier went up a study showed that while all suicides were eliminated from the Ellington, the rate at the Taft barely changed, inching up from 1.7 to 2.0 deaths per year.  What’s even more interesting is that the total number of jumping suicides in Washington dropped by 50%, or the exact percentage the Ellington had previously accounted for. So people stopped from jumping from the Ellington did not jump from other locations.

Coming back to our model that small external factors can have large influences on behavior, you might wonder why the Ellington was the suicide bridge instead of the Taft.  It turns out that the height of the railing was what made the difference. The concrete railing on the Taft was chest high, while the concrete railing on the Ellington (before the barrier) was just above the belt line.  One required a bit more effort and a bit more time to get over and this tended to reduce the impulsive action of jumping.

Which brings us to guns. Although guns account for less than 1% of all American suicide attempts, because they are so lethal, they account for 54% of successful suicides.  In 2005 that meant 17,000 deaths.  It turns out there when you compare states with high rates of gun ownership to states with low rates of gun ownership; you find that there is a direct correlation between the rate of gun ownership and the rate of gun suicide.  This is not surprising.

What is more surprising is that in the states with low gun ownership, the rates of non-gun suicide are the same as those states with high gun ownership.  So the lack of availability of guns does not encourage people to find other means of harming themselves.  Studies show that the total suicide rate in high gun ownership states is double that of in low gun ownership states.  So the Supreme Court, in their recent ruling regarding Washington, D.C.’s ban on handguns, may have missed the more important data when they focused on homicide rates.  From these studies scientists conclude that a 10% reduction in firearm ownership would result in a 2.5% reduction in the overall suicide rate.

I am not anti-gun. I like shooting, and if I were a hunter, would probably own a rifle.  But this is why I don’t own a gun, and this is why I don’t recommend that most people own a gun.  All of us are potentially subject to dark moments of the soul, and the research detailed in this New York Times article suggests that the more barriers and impediments there are to impulsively harming ourselves, the less likely we are to try.  If you do own guns, at least try to create barriers and delays such as keeping the guns locked up in a gun safe, keeping ammunition separate from the guns, or even not keeping ammunition in the home where guns reside.  Not only does this protect you from those dark moments of the soul but it may also protect someone you love, your spouse, or your child.

Again, I highly recommend a careful reading of the original article, as it has much other information that is useful and interesting.

In answering the question of the title, I have to say that reading this article convinced me that we should build a suicide barrier for the Golden Gate Bridge. Yes, it would lower the beauty of this gorgeous bridge, at least for pedestrians, but I have to believe that saving another 2000 lives trumps a pretty walk across the Bay.

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