Evidence act

Admittedly, this is a moot court query. It is the best course to find the answer yourself.

The person who created fake certificate is held liable for the offences of forgery and fraud.

His brother cannot claim innocence stating he never knew that it was fake because he knew the fact that he didn't belong to that caste hence he also can be held liable for this offence.

T. Kalaiselvan,  What If they had no Any Evidence Of their Caste . What If They Were Never Used Their Caste in Any Where. Ex Aadhar card , pan Card , school leaving Certificate , Collage certificate And not even in  Ration Card Then Tell Me How Prosecution will going To prove that fact that they had reason to believe it was forged document . 

yes.he is also guilty for relying as well acting upon the false document-

Purnanand sir the question is Not he Used such false document or not the question is if wasn't aware of such document then is he guilty or not . If he is guilty then The  issuing authority also guilty for issuing such certificate . 

The claim that he wasn't aware of the nature of document he procured will not be acceptable in law because ignorance of law is not an excuse 

Exactly...the issuing authority is also guilty..for relying on false documents...having means n competency to check..