The Federal Records Act does not allow government employees, or contractors, to use a private server for government business.
Using a private server would allow any government employee, or contractor, to sell confidential documents to the highest bidder without the government ever knowing.
Government employees also are not allowed to self-determine what e-mails to delete, or keep … someone from 'IT archiving' has to determine that.
If you ever get a government document sent to your private email account, or a hard copy sent to your US Post Office mailbox, you are supposed to immediately forward the electronic document to your "dot.gov" government account (Hillary never used her dot.gov account) or bring the hard copy to 'IT archiving' within 20 days (she didn't do that either).
What Hillary did violated the law and her own directives to all State Department employees.
Hillary used her private server to evade Freedom of Information Act requests.
And so far she has succeeded -- she went through the e-mails and destroyed most of them -- about 32,000 out of 62,000.
Then she printed hard copies of the 30,000 she decided to return to the State Department, and destroyed the electronic files for all the e-mails.
If the e-mails were revised before printing them, the FBI would have to get files from people who sent then (or received them) for direct comparisons.
If her name was not Hillary Clinton, she would have already been arrested, indicted, convicted of multiple felonies, and possibly spending time in prison.