Personal references are protected, to the extent that liable and slander laws would apply.

Any HR person / lawyer will tell you providing a negative review of an employee, let alone with amount of detail, opens you up to liabilities that aren't worth it.

As an employer, I've been told that, if called, I should only provide the date a person started with the company, the date a person left, their starting and ending salaries (murky now given salary history laws) and whether they'd be eligible to be re-hired.

I ask any employee we fire for cause not to list us as a reference.