For years, calling 911 in Detroit has been a gamble. The average response time to the highest-priority calls stretched sometimes to nearly an hour. Wayne State’s department promises a 90-second response to calls within its territory.

Nefertiti Harris, the owner of Textures, a beauty salon, recalled the afternoon she spotted a man rifling through cars parked outside her store. “I bolted out of the salon, and he ran down the street,” she said. “Then I called Wayne State. They were there within two minutes. Five minutes later, they had him.”

Many of the area’s retailers have similar stories. Rachel Lutz considered several city locations for her first boutique, the Peacock Room, which opened in 2011. Midtown’s security was the deciding factor. A single woman, she says she wanted to be in an area where she would feel safe leaving her shop alone at night. She also wanted somewhere she could display her wares in a sidewalk-facing window without inviting vandalism.

“If you go into a gas station with a bulletproof window, it sends a message,” she said. “That’s not what I wanted for my store.”

Wayne State’s officers had helped out residents and businesses surrounding the school for decades, but in 2009, the university did something unorthodox: It expanded the department’s purview to cover all crime calls in a four-square-mile territory that encompasses both the campus and all of Midtown. At most schools, security officers only operate off-campus when crimes involve or affect students or faculty members.

The goal, university officials say, was to draw new residents to the area and assuage students’ No. 1 concern about living there.