Plaintiff and defendant have the same attributes I am working on my final year project, "civil case management system" related to civil law.

I have a problem to store attributes for both plaintiff and defendant. They have the same attributes. I am not sure what is the best solution.
As you are managing cases, you may want to ensure you don't double book people.  A person could be a Plaintiff on one case and Defendant on another.  I would have a persons table (legal persons like corporations can be problematic), and use a join table to associate persons with cases.  The join table would have a flag to indicate the role in the case.

This model could be extended to cover judges, lawyers, clerks etc.