Sally Yates (DOJ)

Served as US Deputy Attorney General, the second-highest-ranking position in the Justice Department, during the final two years of the Obama administration, under Attorney General Loretta Lynch.
Served as Acting Attorney General, when President Trump took office and Loretta Lynch resigned.
Raised concerns about National Security Advisor Michael Flynn’s contacts with Russia.
Terminated for refusing to enforce Trump’s executive order temporarily banning any immigration from seven Muslim-majority countries.
The AG position was subsequently filled by Jeff Sessions.