Western Pennsylvania has lived through 2009 in an almost permanent state of mourning. There were the Stanton Heights police shootings, the LA Fitness shooting, and now this: Penn Hills police officer Michael Crawshaw was gunned down in his patrol car Sunday night, awaiting back-up. 

This crime will stir up the inevitable debate over gun control, as it has before. Monday afternoon, the gun-control advocacy group CeaseFirePA released a statement asserting, "This is not a day for rhetoric" -- then adding, " ... but the senseless carnage caused by gun violence ... cannot be ignored."

If history is any indication, though, it will be ignored. CeaseFire notes that six officers have been killed across the state this year. But God willing, the number of police killed will remain lower than the total in 2008 and 2004: Seven Pennsylvania officers were killed in both of those years. Yet gun laws have remained unchanged. 

And maybe the problem isn't just the guns. 

The CeaseFirePA release notes another worrisome trend. "Assaults on police in Pennsylvania have increased by 76 percent [since 2002] -- a horrible statistic," asserts the group's executive director, Joe Grace.

In a phone interview, Grace told me the number was based on claims made by Gov. Ed Rendell and other state officials. Rendell actually cited a slightly different stat: "The number of assaults [on] law enforcement officers with firearms in Pennsylvania has increased by 76 percent between 2002 and 2007 [emphasis mine]." But the overall rate of assaults on police -- ranging from fatal shootings to drunken dipshits punching an officer during a DUI -- have been on an upward trend.

According to annual Uniform Crime Report data compiled by the Pennsylvania State Police, police reported nearly 3,600 assaults in 2008. That's a sizable increase from the 3,132 reported from the year before. In fact, for the past five years, there have been an average of 3,136 assualts on officers each year. That's more than a 9 percent increase over the annual average in each of the previous five years.

In other words, police aren't just being subjected to more firearms-related violence: They're reporting more attacks of all kinds.

And for the past couple years, the reports show, Pittsburgh has had the state's highest rate of assaults on police. 

A caveat: "uniform" crime reports are sometimes anything but. Different departments can report data in different ways, and numbers might fluctuate not because of a change in crime rates, but in how departments record them.

And in any case, Grace had no explanation for the trend. "I can't tell you there's been a report or an analysis of that," he said.

The horrific high-profile crimes we've seen this year don't lend themselves to easy theorizing. Police say the Crawshaw shooting stemmed from a dispute over drug money, and that it was carried out by a parolee whose long record -- and ankle monitoring bracelet -- had little effect on his criminal behavior. In Stanton Heights, meanwhile, accused shooter Richard Poplawski may have been motivated by anti-government rhetoric. Other than standing accused of depraved acts of violence, it's not clear what these suspects have in common.

The fact that Penn Hills suspect Ronald Robinson was out on parole means that we will likely hear a clamor for harsher sentences, and more restrictive parole. If Robinson is guilty, no sentence could be too long. But in general, throwing more people in prison doesn't seem to make police any safer.

The Pew Center reports that Pennsylvania's prison population has jumped by more than one-fourth in under a decade. Yet reported assaults on police have been as high as they've ever been. On the other hand, the Center also reports that prison rehabilitation programs are ineffective ... and that the number of people returning to prison for violating parole has increased by more than one third in recent years.

Is there some connection here, between an increasingly punitive society and an increasing amount of violence directed at police ... those men and women who represent the full force of the law -- but who are often just brave, lonely individuals waiting for back-up out in the street? I don't know. Maybe there's no way to explain this sort of madness. Maybe there's no way even to talk about it, except in terms of grief and vengence. 

And yet something in us keeps looking for answers.