Can I file a case for illegal appointment by the government department

I would like to know about illegal appointment done by government department. Department XYZ adevrtises 2 vacancies against a post and conducts written examination against the same. After the written some candidates are shortlisted for interview. I was one of the candidates who was shortlisted for interview. Finally Two candidates are selected against 2 vacancies. My rank was 5 in the final list. One of the candidates who was selected had an invalid degree. And i am planning to go 4 a case agaist the illegal appointment as tge degree is not valid. Will i b benefited if i register the case.