"Anytime you take a life, there's nothing more serious than that and we'll thoroughly investigate everything," Ramsey said.
In each case, officers say they encountered armed men who pointed their handguns at police.
Relatives of one gunman claim police shot an unarmed man, even though a gun was found next to his body.
Ramsey makes no apologies.
"This isn't television. If someone points a gun at you, you don't have to wait to get shot in order to shoot back. It's just real," Ramsey said.
Shootings by police are at a 10-year high. Philadelphia police shot 52 suspects last year. 15 died from their wounds. That was an increase of nearly 50% from 2011. In the last 5 years police have fatally shot 65 people.
For David Rudovsky, a veteran civil rights attorney, these numbers are troubling.
"Some of that can be explained by higher crime rates, a bit more people carrying guns in Philadelphia, and if that's the reason that could explain it. But over the years we have seen a number of shootings where that was not the situation, guns were not in the hands of the persons who were shot," Rudovsky said.
Philadelphia's rate of cops shooting suspects is higher proportionately than many other major cities.
John Maxwell, a former top commander with the Philadelphia Police Department, now teaches criminology at Drexel University.
"The review is very thorough. It's not something that's taken lightly. It's not a culture in the police department that we can shoot and no one is going to say anything," Maxwell said.
"We've got a lot of guns on the street, people carrying guns for whatever reason, and you cannot point guns, you cannot shoot at other people, you cannot do these kinds of things," Ramsey said.