This week marks the annual week-long recognition of some of our nation's bravest heroes. Started in 1962 by President John F. Kennedy, Police Week honors federal, state, and local law enforcement officers who have been killed or disabled in the line of duty.

As the U.S. attorney for the Eastern District of Pennsylvania and the mayor of Philadelphia, we write not only to honor our fallen and disabled law enforcement officers, but also to recognize the daily sacrifices made by all officers, including those of the Philadelphia Police Department.

Philadelphia's is the nation's fourth-largest police department, with more than 6,400 sworn members and 800 civilian personnel. Thankfully, most officers will never be called upon to give their lives in the course of their duties – but every officer is willing to do so each time he or she goes to work. Assuming this risk is itself a profound sacrifice.

Officers who are not physically injured on the job can nonetheless face mental and emotional challenges dealing with the stress and dangers inherent in police work. The families of law-enforcement personnel can also face these same issues. Moreover, in today's divisive political climate, officers face other great challenges, such as increased protests and the effects that a few negative actions can have on the perception of an entire department.

Philadelphia residents deserve safe neighborhoods where they can live, work, and play without fear. They deserve law enforcement's best efforts and compassion. And in return, law enforcement deserves the community's respect and support.

Cultivating positive relationships between police and the community is a top priority for the Philadelphia Police Department. For example, officers participate in a variety of youth-oriented activities, including programs offered at the 21 Police Athletic League centers across the city, the Police Explorer Cadet Program, and drug and gang resistance education for elementary and middle school students. Every district takes a unique approach to engage with its local community through activities like movie nights, block parties, and holiday events. We wholeheartedly support these efforts.

Moreover, it appears that these efforts are already paying off. Violent crime is down 9 percent this year as compared with last year, while homicides are down 5 percent. We also expect continued progress in the reforms instituted by our great police commissioner, Richard Ross, designed to eliminate pedestrian stops without reasonable suspicion. Philadelphia police have also embraced transparency, posting crime statistics on their official website and using social media to connect with the community.

While our collective support and appreciation for this hard-won progress is sincere, it is not blind. We have zero tolerance for any form of corruption or excessive force in the Philadelphia Police Department, and we will continue to insist on accountability for any such actions. The vast majority of officers, however, do not engage in such behavior. For example, under the leadership of Commissioner Ross, officer-involved shootings have decreased significantly.

In 2012, there were 59 officer-involved shootings in Philadelphia. In 2017, there were 14, marking a 76 percent decrease. This is a result of improved training, internal accountability, and an ever-present commitment to public safety. The Philadelphia Police Department has also made foot patrols a staple of its policing. This shows citizens that the police are responsive and available for developing meaningful relationships with residents — not just in an emergency, but in everyday life.

It is the determination, hard work, and bravery of the Philadelphia police that will continue to chip away at the violence that threatens our city. This is not an easy job, and we thank them for assuming this crucial responsibility. We owe them a debt of gratitude for their service during Police Week and every week.

William McSwain is the U. S. attorney for the Eastern District of Pennsylvania. Jim Kenney is mayor of Philadelphia.