Discrimination: Will an Employer Seek Discovery of an Employee's Email in a Discrimination Lawsuit

My question involves labor and employment law for the state of: New Jersey.

Is it common for personal emails/home computer to be ordered searched during discovery ?

What is a consequence if you were to clean some email from your personal email accounts and files from your home computer. This is not to hide anything but if they have a personal nature which you don't want to show during Discovery. For instance email to your wife etc... ?

Discrimination: Will an Employer Seek Discovery of an Employee's Email in a Discrimination Lawsuit