William B. Evans (born February 23, 1958) is currently serving as the executive director of public safety and chief of police of Boston College.

Evans served as interim commissioner from November 2013 until he was permanently appointed by newly elected mayor Marty Walsh.

He is also a graduate of the FBI’s National Academy, FBI's National Executive Institute , Department of Homeland Security Post Naval Executive Leaders Program and received several certificates from the Kennedy School of Government at Harvard University in subjects ranging from homeland security to preparedness leadership.

He was raised by his four older brothers, the eldest of whom was Paul, who is the current executive vice president of security and compliance for Suffolk Downs and former Boston Police Commissioner, 1994 - 2003.

He worked in administrative positions in the department's District Four in the South End at night and attended class at Suffolk University during the day.

He spent five years as a patrolman, during which time he was awarded the BPD's Medal of Honor for his role in apprehending an armed robbery suspect following a high-speed chase.

[5] To smooth over relations between the schools and the Police Department, Evans took college administrators on ride-alongs, addressed students during orientation week, and pressured landlords to pay closer attention to troublesome properties.

Under Evans, the department secured a perimeter around a 20-block radius, swept the scene for secondary devices, and began processing the evidence.

[10] When President Barack Obama came to Boston to attend an interfaith service at the Cathedral of the Holy Cross, Evans and his team were responsible for securing the area.

Shots rang out at one point during the standoff and Evans commanded the officers to hold their fire, as he wanted to take Tsarnaev alive for information.