Psychological pressure over an employee to resign. What should he do?

Hello,

My question is about verbal abuse and psychological pressure over an employee with the final goal to push the employee to resign.

That continued for nearly a year and resulted in serious health issues. The person resigned and is still not able to go back to work due to poor health which resulted from the continued mental pressure and stress for a period of almost a year.

What can the employee do against such injustice as per the new law?

Thank you in advance!