For about 20 years, the “broken window theory” has prescribed this obvious scenario: If a broken window is allowed to remain, the rest of the house will fall into neglect. In short: If somebody doesn’t care for the community, the community eventually won’t care for itself.

This theory has many followers and almost as many detractors. It’s one of those hypotheses whose simplicity is almost unsettling. A problem has been a lack of data proving that what is believed is actually true. Until now.

A new study by Harvard and Suffolk universities done in Lowell, Mass., tested the theory over three years. Seventeen high-crime areas were targeted for community enhancement, code enforcement, cleaning up and greater police presence and patrols.

Seventeen others were left alone. The results showed areas given attention improved greatly, with fewer incidents of crime or blight, while the others were unchanged. While this seems obvious, for theory supporters, it was a proverbial “Eureka!” moment.

Police in Lewiston-Auburn are some of those supporters. They’ve subscribed to broken window theory-based ideas for years and credit its law enforcement spinoff – community policing – for breakthroughs they’ve had in reducing the overall crime rate in the cities.

Yet the Lowell study found policing alone is not enough. Police cannot be responsible for executing the local programs or nuanced enforcement necessary for success.

There must be municipal involvement, which is also here. The cities have made downtown a priority, through code enforcement, development and renewal. Relations with the neighborhood can sometimes get strained, but regardless, attention is being paid.

Again, though, just government and police are helpful, but not enough. Both can start and sustain initiatives, but it’s the third piece – community involvement – that makes them work.

Here L-A has lacked, but not for lack of effort. Rather, lack of direction is the culprit.

Numerous ideas exist for improving the downtown. Many plans, proposals and concepts have come from visioning, charrettes, public hearings, strategic planning sessions, roundtables, workshops and behind-the-scenes scheming.

Unity, however, has been elusive. Fixing broken windows could bring everyone together.

Many downtown desires exist, such as riverside bistros, green space, bars, restaurants, housing, hotels, conference centers. Getting to this future from today, however, will require some rolled-up sleeves and determination on the community level.

Downtown advocates have sparked some of this, but the burden is ultimately on residents and property owners. The city and police are doing their part, but the future universally desired for these neighborhoods needs the involvement of all of its stakeholders to achieve.

The broken window theory works. It’s used here, but with limited success, because more attention is paid on deciding what’s best for downtown, instead of what’s next, while allowing the expectation to exist that somebody else – the police or the city – will make it work.

None of this is effective, because its key ingredient is missing: a community. The secret to fixing broken windows isn’t found in a police station or city hall.

It’s found in their reflection.