"Contact tracing is a service to patients and their contacts to provide services for patients and warning for contacts. It has nothing to do with police activity. Nothing," said Frieden, who is now president of Resolve to Save Lives, a nonprofit that works to prevent epidemics. Galea said he hopes many people will separate in their minds the contact tracing done by public health workers from crime investigations by the police. But, he added, “I do think sometimes it's difficult to make a distinction when you feel marginalized by, and targeted by, the entire government.”