Before joining the Atlanta Police Department as a patrol officer in 1995, Chief Shields worked as a stockbroker in Boston.[6][7] She was the second woman to lead the Atlanta Police Department, and the first openly gay person to do so.[7]
On December 1, 2016, Atlanta Mayor Kasim Reed announced that he had selected Shields to succeed Chief George N. Turner, who was retiring.[8]
In May 2020, amid protests in Atlanta in response to the murder of George Floyd, Shields said that the angry reaction was understandable, and that the value of the lives of black people was being diminished by police or other individuals, stating that such events were a "recurring narrative". She added with some suggestions on how police could do better, namely better training and "weeding out bad cops", and praised the use of body-worn cameras.[9] Shields addressed demonstrators stating that she was happy to allow protests so long as they didn't violate laws. She stated her opposition to using force to halt the protests, stating that protestors have a right "to be upset, to be scared, and to want to yell".[10]
On June 13, 2020, Shields resigned after a video went viral of an officer fatally shooting a black man, Rayshard Brooks. During his arrest for DUI, Brooks wrestled officers, grabbed a taser, and aimed it at the pursuing officers.[11][12][13][14]
In January 2021, she joined the Louisville Police Department.[15]
In June 2023, she joined Georgia-based provider of training tools for law-enforcement agencies InVeris as Chief Commercial Officer (CCO).[16]