Am I reading this correctly: http://www.politifact.com/truth-o-meter/article/2015/mar/12/hillary-clintons-email-did-she-follow-all-rules/ Which states:

"Cox said the fact that Clinton’s staff -- rather than a State Department federal records officer -- chose which emails to destroy is "honestly breathtaking." Her private employees don’t have the authority to decide what does or doesn’t count as a federal record."

So why did Hilary Clinton's staff get to decide what emails to send to the FBI? Why didn't the FBI just get a warrant to retrieve these emails?