Philadelphia is turning the corner on crime.

The latest statistics show sharp decreases in almost every major offense, led by homicide, which is down 30 percent this year compared to the same period in 2012.

It does not end there.  The city also has seen double-digit decreases in other major crimes, including robbery and auto theft, and smaller but significant declines in such crimes as aggravated assault and burglary.

At the beginning of July, of the 14 types of major crimes that police track on a weekly basis, nine were at their lowest levels in the last five years.

In looking for the reasons why, experts point to a number of trends. For starters, Philadelphia is riding a tide — crime is down in many big cities, not only in the U.S. but also overseas.  For another, broad demographic trends are at work, including fewer people in the crime-prone ages of 18 to 29.

Law enforcement officials look at these numbers and see an additional cause: Smarter policing that is data driven, proactive and community centered.  It is policing that relies on the best of the new, such as computer analysis that hones in on ‘hot spots,’ with the best of the old, including a revival of foot patrols.

Kevin Bethel has lived through the changes in policing.  He graduated the Police Academy in 1986. Today, he is deputy commissioner in charge of the department’s patrol operations.

“When I came on, you were given a nightstick and handcuffs and Slap Jack told to go out and police,” he told me. “Today that has changed substantially…the paradigm has shifted.”

To hear a police official use the word paradigm is, in itself, a paradigm shift.

The old world of policing relied mostly on gut.  Now it is being informed by academic research — albeit practical, result-oriented research — which tests crime-fighting approaches with scientific rigor.

The local epicenter for this approach is Temple University’s Center for Security and Crime Science, headed by Jerry Ratcliffe, a former police officer in his native England who turned to academia after a climbing injury ruled out a future in the police.

Ratcliffe arrived in Philadelphia in 2003 and has been working with increasing frequency with the Police Department, particularly under Commissioner Charles Ramsey.

A turning point came in 2009 when Ramsey approved a summer-long experiment in patrolling.  It was a random study that centered on the efficacy of foot patrols.

Foot patrols were once the norm in policing.  Gradually, they had been abandoned in favor of patrol by car.  The assumption was that while foot patrols might make local residents feel better about the police and reduce their fear of crime, they had little or no effect on crime itself.

The Foot Patrol Experiment proved that assumption wrong. In the areas where foot patrols were used in the 2009 study, violent crime went down by 23 percent.

Ramsey and top police officials embraced those findings and foot patrols have become an important part of policing strategy.

Success, though, was built on more than a revival of police officers on foot.  What we are seeing today is the end result of a 20-year process that has changed policing. In Philadelphia, it began in the 1990’s with Compstat, the data-based approach to fighting crime. It included more emphasis on community policing to break down the ‘us-vs-them’ thinking that permeated both the community and police. It also embraced the ‘broken window’ theory of crime prevention that calls for police to pay more attention to quality-of-life crimes.

Today, the data and maps rendered by Compstat in the 1990’s look crude compared to the astonishing array of deep, real-time data that can be called up on police laptops.  (As part of the shift, a number of districts now have police officers assigned to work fulltime as data analysts.)

“There has been a very big shift within the Philadelphia Police Department,” said Ratcliffe, who admires the district’s approach and whose center helps train the district analysts. “It is much more about what the data is telling us, as opposed to what your gut is telling you.  They are better able to identify hot spots and hot times and they are actually getting better at identifying hot offenders as well.”

When it all works in sync, we get policing that is more proactive than reactive and places more emphasis on prevention rather than racking up a high number of arrests.

It helps that police leadership today, many of them now in their 40s or 50s, are members of a generation that grew up with — and grew comfortable with — these new approaches.  They believe these approaches work.

One of those believers is Joe Bologna, a cop since 1990 and now commanding officer of West Philadelphia’s 19th Police District.  An energetic man who exudes an enthusiastic can-do attitude, Bologna became captain of the 19th in June 2012 after serving a stint as head of the department’s South Street police unit.

He inherited a tough job in the 19th, a rough-and-tumble district that has the usual panoply of urban problems: Poverty, blight, drug-dealing, gangs and lots of violent crime.

In his office, Bologna has a picture of Mayor Frank Rizzo, who personified the macho cop style of criminal justice when he was police commissioner.  Rizzo never saw a problem that couldn’t be solved with a night stick.

His homage to Philadelphia’s first Italian-American mayor aside, Bologna personifies the new style of law enforcement. “Times change and if you don’t change with the times, you are stagnant and die,” he told me when I stopped by the district last week; using one in a series of aphorisms he used to explain his philosophy of policing.

Bologna has a large map of the 19th in his office, stuck with multi-color pins, indicating the location of crimes he wants his officers to focus on.  He assembled the map using two years of crime data — yellow pins for burglary, red for robbery, etc. — and deploys a half-dozen foot patrols, mostly on weekends, in these key areas.

“I want boots on the street, out of the metal box [a patrol car] and into the community,” he said.

He preaches the gospel of community engagement and encourages his officers to concentrate on figuring out what can be done before they employ the enforcement option.

“I preach to the troops: ‘Work on the little stuff and maybe we’ll stop the big stuff from happening.'”

A Bologna riff reveals his approach.

“This is a large district and we can’t be everywhere, so we need community support in getting information so we can target our patrols. I ask my people: ‘How would you solve a problem if we had no personnel?’

“Say 49th and Thompson we know they are selling drugs on corner.  What can we do with that area to displace them? What can we do without using our people?  Do we need to use 311 to get better lighting? What about trees? Are they overgrown?  Can we get Streets to cut them back? Is there blight? Maybe if we clean and seal a building it will help.

“If you take care of that stuff first maybe that problem will disappear. If we try all of that stuff and we still have an issue there, we will hit it with enforcement. I want enforcement as our last strategy.”

Outside his office, in the district’s roll call room, Bologna has large district maps on one wall that mark off hot spots and arrests.  On another sits a large flat-screen TV that flashes up pictures and information of suspects and policing alerts.  Bologna uses his Blackberry to push out emails to his officers and neighborhood leaders, informing them of matters large and small.  Apparently, he sends out a lot.  When he returned from California recently after a vacation, one of his officers told him they knew he was gone because they didn’t get their daily dose of emails.  “They call them Baloney Blasts,” Bologna said, laughing.

On another wall there are sheets of paper on a cork billboard that from a distance look as if they could be the rosters of neighborhood softball teams, carrying such titles as 56th and Master; 4900 Thompson; 62nd and Callowhill and 5000 Lebanon Ave.

Looking closer, I realized they were local gangs, identified by the epicenter of their turf.  Each page carried a headshot and basic information on each gang member, including photos of the tattoos gang members favor. “They know we know them,” he said.

Bologna is proud of the fact that the lists were developed by his officers from information they gained on foot patrols and contact with the community. He said he wanted all of his officers to be involved in intelligence gathering.

“More than 90 percent of the people in this district are good people,” Bologna told me. “It’s a small percentage of guys who do bad, so we pay attention to them. They don’t like attention.”