How Security Lights Can Make You Unsafe

Halloween draws near and with it brings a prime opportunity for you to take note of the glare and of the false sense of security brought about by the so-called “security” lights that pervade your neighborhood.

There is nothing inherently wrong with using lights at night to increase your security and ability to function in your environment.  However, the means of deploying these lights leaves much to be desired, often times having the opposite of the intended effects: reducing your security and ability to fully function during the night.

Why is this and how did things get so bad?

Stores that sell you “security lights” are not in the business of selling security.  They are in the business of selling Lights.  It is a common misperception that more light means more security.  Studies have shown that the opposite is often true.  But people look to the night and are afraid of the dark.  They turn to bright lights and, much like a moth, feel safe.  This is an emotional response not backed by intelligence.  Advertising targets your gut, not your brain.

According to a British organization dedicated to Intelligent Lighting Design and Use:

"Lights can help criminals see what they are doing, and help them to see an escape route in what would otherwise be unfamiliar surroundings. Burglars no longer need to carry a torch!"

"Ironically, there is no evidence that installing a "security floodlights" will make any area more secure; some people have been broken into directly beneath such floodlights."

Glare from improperly shielded lights can have a major negative impact on your security.  Glare creates “hard” shadows in which people can hide.  Your pupils quickly close down upon detection of a point source of light (like night blindness) killing your night vision and blinding you to potential threats.  Take a look at the images to the right for an example.

Nobody notices a person walking on your property at night even if it’s well lit.  However, people do notice a light that turns on, like a motion sensor controlled light.  In fact, lighting up the ground all of the time allows anyone entering your property to see and avoid the obstacles present (rocks, unwound garden hose, children’s bike, etc…).  Criminals do not fear the light; they avoid the dark and fear the change from dark to light.

Studies done across the world have come to this conclusion.
A report about when the UK Home Office (Government Branch that deals with Homeland issues) performed a study on what deters burglars:

• Belief that house is occupied (84%)
• Presence of alarms outside property (84%)
• Presence of CCTV/camera nearby property (82%)
• Apparent strength of doors/window locks (55%)
• Other factors include convenient approach and exit routes and there being a ready market for the goods.

Nowhere in the report is the presence of lighting mentioned as a deterrent.

Back here in the USA in Chicago, an illuminating study measured the effects of additional street lighting on crime.

"For the six month period prior to the … lighting improvement, the experimental area showed 205 reported incidents in the pre-period and 287 in the post-period – a 40 percent increase. Each crime category (violent Index, property Index and non-Index) showed an increase…"

Not a decrease in crime, but an increase.

But if increased lighting increases crime, does decreased lighting decrease crime? 

In response to a budget crisis in 2004, Des Moines IA turned off their streetlights.  Were there waves of crime as a result?  Quite the opposite.  According to the Des Moines Register

"The first four months of 2004 saw a 3.5 percent drop in vandalism, burglary and robbery," and "we've observed no significant increase in crime in the areas
where the lights have been turned off," Police Maj. Dale Patch said.

The same that holds true for municipalities holds true for local security lights.

According to a a report the Battle Ground School District in the state of Washington “has reduced vandalism to almost zero with a policy to darken campus after 10:30 p.m."

Even the National Institute of Justice, in a 2006 report, concluded that

"The problematic relationship between lighting and crime increases when one considers that offenders need lighting to detect potential targets and low-risk situations. Consider lighting at outside ATM machines, for example. An ATM user might feel safer when the ATM and its immediate surrounding area are well lit. However, this same lighting makes the patron more visible to passing offenders. Whom the lighting serves is unclear."

In fact, according to the Guardian Newspaper, "it may not be too fanciful to make comparisons with our medieval ancestors' measures against witchcraft - tokens hung over the door and so forth," when trying to explain the attraction of most people to security lighting systems that will, in fact, reduce their safety and security.

What can you do about it?  If you are planning to install or retrofit security lights for your property do the following:

Clearly define the area on your property that you want lit

• Get lights to specifically cover those areas.
• Get lights that only cover those areas

Get a fixture that shields stray light

• These carry reflectors that increase the performance of whatever light is inside them, directing light to the target area and in such as way as to eliminate the “dazzle” of glare.
• By the nature of their design, these fixtures are more energy efficient than non-shielded fixtures - this saves you operating costs.
• Some Examples: (I have no affiliation of any nature with the companies listed below)
  • A popular fixture
  • A list of about 50 companies selling various properly shielded lighting fixtures

Get an infrared motion sensor to control the operation of the light.

• These IR sensors can be tuned to respond to humans, but not to cats, dogs or raccoons
• The change from dark to light alerts you and your neighbors about something suspicious.

Avoid “Dusk to Dawn” timers at all costs.

• Do you really want to help someone at your door/window at 3AM to see what they are doing?

Perhaps another report by the UK Home Office sums up the effects of lights on crime when it says:

"Better lighting by itself has very little effect on crime."

This same study goes on to say that what increased lighting does improve is the Public’s perception of safety.  So if you want to feel safe, but not actually be safe, keep adding “insecurity” lights.  If you want to actually be safer, put some thought into proper outdoor light shielding and an infrared motion sensor.

This Halloween, as you are walking your neighborhood, take a look around the glare from your local “insecurity” lights, and see the harsh shadows they create.  Waiting in there is where you will find the real monsters.