Report 203 · Luxury Home Security
More light is the most common answer to a crime problem, from city councils to estate owners. A new study of Newark's LED street-light retrofit found a real effect: nighttime outdoor violent crime near the new lights fell about 46 percent. For six months. After that it faded, and over two years there was no significant reduction at all.
Lighting comes up in almost every home-security conversation I'm part of, and the instinct behind it is reasonable. Light helps people see, helps cameras see, and seems to tell an intruder that someone is paying attention. The research mostly agrees that lighting can move crime numbers. What it rarely gets asked is the question that matters for anyone paying for it: how long does the effect last, and on which crimes?
A paper published on 24 September in the Journal of Quantitative Criminology is one of the few that followed the lights for two years. The trade site Inside Lighting summed it up in its headline: the retrofit "Cut Violent Crime, Then Faded." I read the paper itself, which is open access. Here is what it measured.
Between 2019 and 2021, the utility PSE&G, working with Rutgers' Newark Public Safety Collaborative, replaced 1,419 old high-pressure sodium cobra-head street lights with LED fixtures, prioritizing poles in high-crime areas. The research team, led by Alejandro Giménez-Santana, counted every reported crime within 200 feet of each pole, split by day or night and indoors or outdoors, and compared replaced poles with nearby poles that weren't replaced. The 200-foot radius came from the utility's own coverage design for the new fixtures.
One caveat up front, which the authors state themselves: this was not a randomized trial. They write that they "cannot claim that the identified effects can be generalized" to all the city's poles "as the replacements were not randomized." It's a careful quasi-experimental design, not an experiment.
The authors' own conclusion is blunt for a paper that found a real effect. Enhanced street lighting, they write, "should not be interpreted as a 'silver bullet' solution to prevent violent crime." They offer two main explanations: offenders adapt to the new environment, and the things that attract crime in the first place, such as certain corner stores, don't move when the light changes. They also report a third possibility they couldn't measure. Community members said, anecdotally, that some new lights "may have been intentionally damaged following installation to preserve poorly lit conditions," and the study "does not control for the damage to lighting infrastructure." Inside Lighting adds an observation of its own: the paper reports no light-level measurements before or after. Nobody verified how much light was actually on the street in year two.
The study most people cite when they say lighting cuts crime is a randomized trial in New York City public housing by Aaron Chalfin and colleagues. It's a genuinely strong design: 80 high-crime developments, 40 randomized to get lights and 40 to serve as controls. But the details matter. The lights were temporary towers that, in the working paper's words, "emit approximately 600,000 lumens," on timers from sunset to sunrise, for six months. The authors themselves call that "extraordinarily luminous."
The headline was a reduction of at least 36 percent in nighttime outdoor serious crime. The authors then do the math most coverage skips: only about 11 percent of serious crime on those campuses happened outdoors at night, so the overall effect "may reduce serious offending in these communities by approximately 4 percent." They also warn that the towers were "very bright," far more than "a typical investment in marginal lighting would entail," and so prominent that the result "may fold in substantial demonstration effects."
To be fair to lighting, the Newark authors' literature review reports that a three-year follow-up of the same New York intervention (Mitre-Becerril and colleagues, 2022) found the effect persisted. I couldn't open that follow-up's full text, so I'm reporting it as the Newark paper describes it. Put the two together and the honest reading is that lighting can work, sometimes for a while and sometimes longer, and the conditions matter a great deal.
None of this research was done on private homes, and the gap is worth stating clearly. Both studies measured public streets and housing campuses in dense cities, and their strongest effects were on outdoor violent crime like assaults and robberies, not the break-in an estate owner is usually worried about. I can't tell you from these papers what landscape or flood lighting does to burglary risk at a private property. Nobody has measured it this way.
What does transfer, in my view from designing these systems, is the pattern. First, a deterrent that depends on novelty decays, so lighting shouldn't be the whole plan. Second, a light that's broken or dimmed isn't a deterrent at all, so lighting needs the same monitoring as any other sensor; the Newark team couldn't tell whether its lights were still working, and that's exactly the blind spot to design out. Third, light earns its keep most reliably as a support for detection: it's what lets a camera capture a usable image at night, which is a separate question I looked at in Report 155.
I help design the AI security systems for a veteran-owned (SDVOSB) home-security company run by fellow veterans. I do not own that company and earn nothing from this link. Full policy here.
The full New York follow-up. Wiley blocked access to Mitre-Becerril et al. (2022). The persistence finding is reported here as the Newark paper's review describes it.
Published-version numbers for New York. I read the 2019 NBER working paper in full and the published 2022 journal abstract. The quoted figures (600,000 lumens, 36 percent, 11 percent, 4 percent) come from the working paper; the journal abstract confirms the same direction of findings.
Anything about private estates. No study cited here measured residential property lighting or residential burglary at single homes.
Brighter lights can cut nighttime outdoor violent crime, and the best evidence says so. The newest and longest look, from Newark, says the effect can also fade within a year, possibly because offenders adapt and possibly because the lights themselves stop doing their job. The New York trial that made lighting famous used towers far brighter than any normal fixture, and its effect on overall serious crime was about 4 percent. For a home, treat lighting as a layer that has to be maintained and paired with detection, not as a fix you install once and forget.
U.S. Army combat veteran (Counter-IED / Electronic Warfare), peer-reviewed researcher in microwave spectroscopy, and founder & CEO of Shroombiosis. Consults on laboratory operations, AI, and supplement formulation.