From his office in Doylestown, 25 miles north of the city that elected the nation's most progressive district attorney last November, Bucks County District Attorney Matthew Weintraub has a particular vantage point.

He sees what's happening in Philadelphia, where officials have worked to reduce the jail population by more than 30 percent over the past few years, and where DA Larry Krasner has ordered staff to seek sentences below the guidelines on many offenses. And he's aware of state-level efforts to reduce a prison population that's finally declining, down 6.4 percent over the last five years, after decades of exponential growth.

It's just that Weintraub doesn't see what it has to do with his job of keeping Bucks County safe.

In fact, rather than reform, he's looking to get tougher: In the last few years, he's been increasingly charging fatal DUIs as third-degree murders as opposed to the less-serious vehicular homicides, and he's slapped two dozen drug dealers with "drug delivery resulting in death" charges.

That may be one reason why, though the crime rate in Bucks County fell by 19 percent from 2006 to 2015, the number of people sentenced to state prison increased by 29 percent. When parole violators are included, the number of people sent to state prison from the county increased 97 percent over that same period.

"We're holding people more accountable for either their malicious intent or the end result of their malicious conduct, and we've been very aggressive," Weintraub said. "Nobody has come to me and said, 'You're sending too many people to state prison in Bucks County.' I think, by and large, people feel protected and safe."

A similar dynamic is playing out around the nation: As incarceration declines in urban areas, it's increasing pretty much everywhere else.

In the commonwealth, from 2000 to 2013, the number of prison admissions from big cities fell by 8 percent, while admissions rose in the suburbs (by 133 percent), in small- and mid-size metros (83 percent), and in rural areas (174 percent). That's according to an analysis from the Vera Institute released this month.

"During a period when crime rates are historically low, you would expect to see incarceration rates dropping," said Jacob Kang-Brown, one of the authors. "That is what we're seeing in some places. In others, there's a surprising trend of growth, which raises a question of whether this continued growth of mass incarceration is really making communities safer."

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Part of what's driving that is prosecutorial discretion — whether the approach is to take a hard line with criminals, or, on the other end of the spectrum, to divert as many of them as possible into treatment programs.

To a lesser extent, observers also cite the growing opioid crisis.

"They're burglarizing stores or homes to get money to buy heroin," said Bret Bucklen, director of research for the Pennsylvania Department of Corrections. "We've seen a doubling in the last seven years in the percent of court admissions who are diagnosed with an opioid problem coming to us."

Then there's the effect of Pennsylvania's largest-in-the-nation population of parolees, including 40,000 people under state supervision.

In 2016, for the first time ever, more people were admitted to state prison on parole violations than on new sentences.

"It's because we're getting more and more people out of prison that we're getting more and more parole violators back," Bucklen said.

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But that alone doesn't explain the fact that you're now statistically more likely be sentenced to state prison from a small town than a big city in Pennsylvania, when the opposite was true just a decade ago.

Today, the highest rate of state prison commitments comes from Jefferson County in northwestern Pennsylvania, where, for every two people arrested in 2015, one person was sentenced to state prison. (The ratio is more than 7-1 in Philadelphia.)

Richard Long, executive director of the Pennsylvania District Attorneys Association, said prosecutors statewide are responding to the opioid crisis with every weapon they have at their disposal.

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"We're trying to figure out who exactly is profiteering at the expense of the health and safety of others," he said. "Those individuals are being targeted."

But also, he said, it's natural that different values would lead to different punishments.

"You have the fifth-largest city in America, and a county next door that has a different character to it that's suburban or small-town. The resources available and some of the norms … those things enter into it as well."

For example, jaywalking may be normal in Philadelphia, he said. "It might be something where, in a small town, an officer might say, 'Hey, you can't do that here.'"

Still, many prosecutors said they weren't aware of an increasing incarceration rate, or disputed that it could be true.

In Lancaster County, where new court commitments increased 61 percent from 2005 to 2016, and parole violations to state prison increased 189 percent, according to Vera's analysis of DOC data, DA Craig Stedman wondered if those numbers were "cherry-picking."

Although the rate of major crime was down 32 percent in the county from 2006-15, "I don't feel like our crimes are down," he said. The number of cases he's filed increased 26 percent in the past decade.

But Stedman said, "It's important to us to get it right. I know I'm diverting more cases than ever before, as far as mental health court, veterans court, ARDs [Accelerated Rehabilitative Disposition]. Before I took over, I could count on one hand how many non-DUI ARDs were given."

He said that just 6.3 percent of cases were diverted in 2005, compared to 22.6 percent in 2016. (That's even more than Philadelphia, which diverted 20.9 percent of cases into specialty courts or other diversion programs last year.)

Prosecutors around the state are doing the same. Even Jefferson County recently inaugurated a drug court.

There's still a belief that tough sentences are needed to deter criminals from reoffending and to set an example in the community.

As Weintraub put it, "We've at least publicly declared that not only are we not going to tolerate this lawlessness, but you will face very severe consequences here in Bucks County if you commit these types of offenses."