If run in any reasonable way she would have had it backed up, but backups preserve information. She did her best to make sure that didn't happen from the start.
To Bogwalker,
Not necessarily. That's my point. She could have well forgotten a backup from several years ago, unless backups write over one another. I don't know what SOP is for backing up computers.
Most criminals don't get caught by Columbo. They get caught for making extremely dumb mistakes. This includes talking without your lawyer. That said, an olde backup could be easily forgotten.
Just sayin'...
Regards,
Doug