Usually you only give immunity if you are getting something worthwhile in the deal. But not here.
Via Weekly Standard:
A congressman says Hillary Clinton’s former chief of staff, Cheryl Mills, and two other staff members were granted immunity deals in exchange for their cooperation in the now-closed FBI investigation into Clinton’s use of a private email server as secretary of state.
Rep. Jason Chaffetz (CHAY’-fits), chairman of the House Oversight and Government Reform Committee, tells the Associated Press that Mills gave federal investigators access to her laptop on the condition that findings couldn’t be used against her. Chaffetz says, “No wonder they couldn’t prosecute a case. They were handing out immunity deals like candy.”