In the 13 years that Marian Hatcher has been working with the Cook County Sheriff’s Office to fight sex trafficking and change the perception of prostitution as a victimless crime, a previous drug charge on her record hasn’t caused her much concern.But a group at The John Marshall Law School has decided she deserves to have that conviction tossed, which has led it to help Hatcher, 55, a sex trafficking survivor herself, seek executive clemency.Currently, they’re waiting for Gov. Bruce Rauner to decide on …