John Gassew, the 23-year-old arrested 44 times by Philadelphia police but never convicted of a crime, was charged today with federal robbery and gun charges.

Gassew, whose previous arrests were mostly for armed robbery, is charged with robbing a 7-Eleven convenience store on Oct. 28, after beating the store clerk with a gun. Philadelphia police shot Gassew after he crashed a stolen truck into a tree and ran from police, they said. Police said they recovered a loaded .45 caliber pistol from the vehicle.

Federal agents arrested Gassew today and prosecutors charged him with violating the Hobbs Act, which targets robberies affecting interstate commerce.

Federal prosecutors have used the act to go after robbers who hit gas stations, convenience stores and other businesses that they can show are involved in interstate commerce.

They also charged him with carrying a firearm during a crime of violence, a federal law that mandates a minimum of seven years behind bars for first-time offenders and 25 years for repeat offenders - on top of whatever they get for the underlying crime.

Gassew had become the face of the failings of Philadelphia troubled court system after his life was chronicled in an Inquirer series in December.

The series found that nearly two thirds of all defendants charged with violent crimes in Philadelphia escape conviction on all charges. The series also found that despite having the highest violent crime rate among major American cities, the city had the lowest conviction rate for violent crime.

Former District Attorney Lynne Abraham disputed the findings saying that conviction rates are a poor way to evaluate the performance of prosecutors because they can be easily manipulated.

By contrast federal prosecutors tend to select cases they are likely top win and enjoy a conviction rate of 95 percent. Tough federal sentencing laws routinely lead to prison terms of 20 years or longer.

Since 2001, federal prosecutors have targeted about 2,000 defendants in the city court system and filed firearms and robbery charges in federal court.

Assistant U.S. Attorney Robert K. Reed, who oversees the unit that handles firearms and robbery cases, has said that he hopes to get this message out that if defendants come into federal court, they will face up to life in prison.

About 200 Philadelphia cases a year end up in federal court under the Justice Department initiative, known as Project Safe Neighborhoods. Many of those defendants had repeatedly won other cases in city courts, where an Inquirer analysis found that even in the most basic gun-possession cases, only 56 percent of defendants charged in 2007 were found guilty of any crime.

Almost all of the federal cases end in guilty pleas. Only about one in seven defendants opts for a trial. Those who do face generally more conservative jurors who are drawn not only from Philadelphia, but also from more rural counties such as Lancaster, Lehigh, and Northampton.