After Pittsburgh homicide detectives arrested a teenager in the March 16 killing near Carrick High School, many wondered how the young suspect got the assault-style rifle used in the shooting.

		Graphic: Pittsburgh firearms violations, 2004, in pdf format

The answer, unfortunately, is that those under the legal age to buy a gun can get one without much difficulty if they know the right people and have the money -- or drugs -- to make the illegal purchase. Or they simply steal it.

Here, as elsewhere in the United States, there's a demand for guns by people who can't buy them from a licensed dealer because they're too young -- the legal age is 21 for a handgun and 18 for a long gun -- or have a criminal history that precludes gun purchases. Pittsburgh police said their arrests show that at least some of that demand is being illegally met.

Police have been trying to combat the trend by focusing on gun seizures. Six years ago, Deputy Chief William Mullen had the federal bureau of Alcohol, Tobacco and Firearms put on a daylong seminar for Pittsburgh officers, teaching them characteristics of armed individuals. Since 2000, the bureau has compiled statistics on arrests for weapons violations in which a gun is seized and the number has jumped every year -- from 269 in the first year to 616 last year.

Mullen attributes the increases to better police work and the fact that there are more guns on the street.

Statistics show that 237 of the 616 people arrested in the city last year on weapons charges were too young to have made a legal purchase. Two of them were 12 years old -- one had a 12-gauge shotgun and the other a semiautomatic handgun.

The weapons could have been stolen by the suspects themselves or sold to them on the street by someone who stole them. Another possibility is they were legally purchased from a licensed dealer and then illegally resold on the street, a procedure known as a straw purchase.

Some straw purchasers report their guns as stolen shortly after they sell them; others only do so after the gun they sold is used in a crime and traced back to them. There is no law requiring a gun owner to report a stolen weapon.

Mullen said the vast majority of the guns seized by police were reported stolen in Western Pennsylvania.

"People were thinking someone was bringing guns here in the trunks of cars but that's just not the case. Seldom do we recover a firearm from outside the state," he said.

While the ways guns are illegally acquired haven't changed much over the years, law enforcement officials are seeing some different twists and are taking new tacks to deal with the problem.

One relatively new phenomenon that is putting guns in the hands of those who can't buy them legally is the bartering of stolen or straw-purchased guns for heroin. Mullen said heroin has become the "drug of choice" over the last four or five years. In fact, it leads all drugs seized by Pittsburgh police by an 8-to-1 margin.

What police are seeing, Mullen said, are heroin-addicted suburbanites feeding their addictions by either stealing or legally purchasing guns and then bringing them to the city, where they trade them for heroin.

That's because those who can't legally purchase a gun will pay a high premium to buy one illegally. Guns sold illegally are marked up to three or more times their retail value. A gun purchased from a dealer for $100 could fetch $300 or more in heroin, authorities said.

This month, a Glenshaw man, 21, came to the East Liberty station with his mother, who told Lt. Philip Dacey she persuaded her son to report a stolen gun.

The man, who Dacey believed was a drug addict by his look and mannerisms, proceeded to tell a story that sounded dubious to the veteran officer. He said he purchased a Ruger 9mm semiautomatic handgun on Feb. 18 and brought it to Pittsburgh to show a friend. He wasn't quite sure where this took place. The gun was under a coat on the back seat of his car and he suspected his friend took it.

"What's your friend's name?" Dacey asked.

"I don't know," the man said. "I only know him as Joe."

"You listen to this and you know what's going on," Dacey said last week. "He traded it for drugs. His mother later admitted to me he was an addict.

"I was so frustrated with him that I said, 'If this gun comes back in a crime I will make it my personal mission in life to arrest you as an accessory.'

"I know what happened here but what you know and what you can prove aren't necessarily the same thing."

Dacey, a gun collector and federally licensed dealer who helped spearhead the local gun buyback program more than a decade ago, said police seize guns in all retail price ranges, from as little at $79 to as much as $1,000. And he noted the considerable street markup. Officers seized a gun that sold for $300 in a store but still had attached a homemade, street-sale price tag of $1,500.

As it has been for years, the street gun of choice is a semiautomatic handgun, which is seen as more desirable than a revolver because it fires more quickly and has a higher ammunition capacity.

In the Carrick homicide case, an assault-style rifle was used. Police said Derwin Milligan, 17, of Beltzhoover, was in a car when he fired the weapon into a parked vehicle, killing 16-year-old Keith Watts Jr. of Knoxville and wounding Watts' friend. Investigators continue to look for the weapon and at least one other suspect in the killing.

Last week, police developed information that led them to an SKS assault-style rifle and 300 rounds of ammunition in Beltzhoover. Ballistics showed the seized weapon wasn't used in the Carrick shooting but, as Mullen said, "we got another gun off the street."

Mullen said assault-style rifles are being used in more crimes but investigators are uncertain whether a trend is emerging. In all of last year, only one of the 47 homicides was committed with an assault-style weapon. That homicide was in December and thus far this year, two of the 11 homicides have been with assault-style rifles, meaning they were used in three of the last 14 city homicides.

"We don't know what this means but we're tracking it," Mullen said.

Generally speaking, rifles aren't desirable street weapons because they can't be concealed, but they are more powerful and accurate than handguns.

"You can't walk around the street with them concealed in your pants; you can't stand on a corner with an AK-47 on your shoulder," Dacey said. "But if you're in a car and you have a specific destination where you are looking to shoot someone, you don't worry about concealment."

Arresting straw purchasers and others illegally dealing in guns is a priority of federal and local law enforcement officials. The Pittsburgh police Firearms Tracking Unit has three city detectives and an ATF agent permanently assigned to it. Pittsburgh is one of about 15 cities across the country given special federal resources, including a computer that traces guns nationally.

Moreover, under a national program, more people arrested on weapons violations are being prosecuted in federal court, where penalties are much stiffer. Additionally, certain repeat criminals can be detained by federal authorities until hearings, whereas suspects are usually released on bond at the state level.

Pittsburgh police said that's necessary because many of the people they arrest on gun charges quickly make bail and are back on the street committing gun crimes. An example, they said, is a suspect arrested three times in four months last year on weapons and other charges who was released on bond each time. After his last release, he emerged as a suspect in a shoot-out on the North Side. Two guns were found nearby.