Gov. Ed Rendell signs a bill into law at the Fraternal Order of Police lodge in Philadelphia, Friday, Oct. 17, 2008. The bill increases the mandatory minimum sentence for anyone convicted of shooting a firearm at a police officer and for crimes committed with illegally purchased guns.

PHILADELPHIA — Pennsylvania's gun laws got tougher Friday as Gov. Ed Rendell signed a bill increasing the mandatory sentence for anyone convicted of shooting a firearm at a police officer and for crimes committed with illegally purchased guns.

Rendell, flanked by family members of slain Philadelphia police officers, city and state officials and law enforcement, signed the wide-reaching bill at the Philadelphia Fraternal Order of Police lodge.

"It's a good day for Pennsylvania and a great day for law enforcement," said Philadelphia District Attorney Lynne Abraham, who pushed for the changes.

Rendell signed the legislation less than 10 days after it unanimously passed both houses in the state Legislature and less than a month after the shooting death of Philadelphia police Officer Patrick McDonald, who was killed by an illegally purchased gun.

"We're doing this in the name of every officer in the Commonwealth who has been shot at, who has been injured, and it is the very least that we can do," the governor said.

Rendell first focused on the portion of the bill that increased the sentence for anyone shooting a firearm at a police officer, which has been raised from 10 years to 20, with a maximum of 40 years.

"I do believe with all my heart ... that mandatory sentences, if well publicized, will cause many criminals to decide to keep that gun in their pocket," Rendell said.

Spreading the word about the new law is key to the bill's effectiveness, said Rendell, who plans to have placards placed in stores and to advertise the increased penalties in television and radio ads.

"If we deter one criminal in one city in Pennsylvania every year from taking that gun out of their pocket and shooting a police officer, this is great legislation," the governor said. "And I believe, if we do it right, we can deter more than one."

Guns have been pointed at Philadelphia police officers 263 times since 2003 and city police have been shot at 188 times and struck 22 times in the same period, according to FOP president John McNesby.

Five Philadelphia officers have been killed in the line of duty since 2003, four by a firearm.

Rendell pointed out that the bill will aid prosecutors on a number of firearm issues. It increases the statute of limitations for prosecuting straw purchases linked to gun crimes from two to five years. It prevents mentally ill individuals from buying guns, raises the penalties for lying when filing federal paperwork to buy a gun and for filing a false report of a stolen gun.

Abraham said an important part of the bill's success in the Legislature was that the National Rifle Association was on-board with the changes.

"Overall, the bill does a lot of great things and has some tools to go after the bad guys, with some protections in there for gun owners," said NRA lobbyist John Hohenwarter.