Why Good Lighting Matters: What a Major New Study Tells Us About Safety and Negligent Security
By Adam J. Langino, Esq.
Why Good Lighting Matters: What a Major New Study Tells Us About Safety and Negligent Security
Most of us have felt it. You walk to your car after dark, the parking lot is dim, and a few of the overhead lights are burned out. Something in you tightens. You move a little faster. You keep your keys in your hand.
A growing body of research shows that good lighting really does make public spaces safer — and when property owners let their lighting fall into disrepair, people can get hurt. A major new study out of Philadelphia puts hard numbers behind what many of us already sensed, and it offers a helpful way to understand why lighting comes up so often in negligent security cases here in North Carolina.
This article explains, in plain language, what the research found, how lighting connects to public safety, and why it matters when a property owner fails to keep visitors reasonably safe.
What the Philadelphia study found
Researchers at the University of Pennsylvania studied what happened when the City of Philadelphia began replacing its old streetlights with modern, energy-efficient LED lighting.1 Over about ten months, the city upgraded more than 34,000 streetlights across roughly 13,000 street segments — about a third of the entire city. The new LED lights give off clearer, more even light and dramatically reduce the dark “gaps” between lights where it is hard to see.
After the lighting upgrades:
Outdoor nighttime street crime fell by about 15%.
Outdoor nighttime gun violence dropped by about 21%.
The researchers estimated the lighting improvements may have accounted for roughly 5% of the city’s overall decline in gun violence during the study period.
Just as important is what did not happen. One common worry about safety improvements is that they simply push crime “around the corner” to the next block. The study found no evidence of that. Crime did not move to nearby streets — if anything, neighboring streets saw a small benefit too.
The study also went beyond statistics. Researchers spoke with residents, who described how dim, poorly maintained lighting made them afraid to go outside at night, and how better lighting made their neighborhoods feel safer and more cared for. As one resident put it, when a space is bright and people are visible, someone looking to commit a crime is “not just gonna be standing there.”
Why lighting makes a difference
The researchers explain the effect in a commonsense way. Good lighting works because it changes the situation on the ground:
It removes hiding places. Even, consistent light eliminates the shadows and dark corners where someone can wait unseen.
It increases the chance of being seen and identified. People intent on wrongdoing tend to avoid places where witnesses and cameras can clearly see them.
It reduces fear, so people use the space. When a street or lot feels safe, more people are out and about — and more “eyes on the street” is itself a natural deterrent.
This is part of a well-established idea that small, practical changes to a physical space can have an outsized effect on safety. Lighting is one of the clearest examples. A decades-long review of earlier studies had already found that better street lighting reduced crime by an average of about 14%. The Philadelphia study is significant because it showed those benefits can hold up across an entire city, not just a single block.
How this connects to premises liability and negligent security
Here in North Carolina, the law generally recognizes that property owners who invite the public onto their premises — landlords, apartment complexes, shopping centers, bars, hotels, parking garages — have a duty to take reasonable steps to keep visitors reasonably safe. That can include protecting people from foreseeable criminal acts by others.
“Negligent security” is simply the name for a claim that arises when a property owner fails to provide reasonable security and someone is harmed as a result. A central question in these cases is foreseeability — put simply, whether the owner knew or should have known that this kind of harm was a real risk. When a property has a history of crime, or sits in a high-crime area, a jury may find that the owner should have anticipated the danger and taken reasonable precautions.
And what do reasonable precautions often look like? Many of the same measures the research points to:
Adequate lighting — enough coverage, with minimal shadows and dark spots, and bulbs that are actually working and maintained.
Functioning locks, gates, and controlled access.
Working, well-placed, and monitored security cameras.
Landscaping that does not create hiding spots.
Appropriate security personnel or patrols where the risk calls for it.
Lighting shows up again and again in these cases for a reason. It is one of the most basic, affordable, and effective safety measures a property owner can provide — and, as the Philadelphia research illustrates, it genuinely affects whether crime happens. When a parking lot is left dark, when burned-out bulbs go unreplaced for weeks, or when lights are positioned so that large areas sit in shadow, that neglect can create exactly the conditions in which someone gets hurt.
Whether any particular property owner acted reasonably — and whether a specific incident was foreseeable — always depends on the facts, and those questions are ultimately for a jury to decide.
What to take away
If you have ever felt uneasy in a dark parking lot, your instincts were sound. Good lighting helps keep people safe, and that is backed by careful, large-scale research. For property owners, it is a reminder that maintaining adequate lighting is not a luxury — it is a basic part of keeping visitors safe. For people who have been harmed, it is a reminder that a property’s conditions, including its lighting, can be an important part of understanding what went wrong.
If you or a loved one has been hurt
If you or someone you love was injured or killed because a property was not kept reasonably safe, you do not have to sort it out alone. These cases can be complex, and the evidence — including records of past incidents and the condition of a property’s security measures — often needs to be gathered early.
At Langino Law PLLC, based in Chapel Hill, we handle negligent security cases throughout North Carolina, and we work on a contingency basis, meaning you pay no attorney’s fee unless we recover for you. When we talk, there is no pressure — just an honest, compassionate conversation about what happened and how we may be able to help.
Please note that North Carolina sets deadlines for bringing these claims, so it is wise not to wait. Call us today at 888-254-3521 or go to https://www.langinolaw.com/contact for a free, confidential consultation.
1. MacDonald, John M., et al. "Can Enhanced Street Lighting Improve Public Safety at Scale?" Criminology & Public Policy, vol. 25, no. 1, 2026, pp. 31–62. Wiley Online Library, https://doi.org/10.1111/1745-9133.70006.