Seeking valuable advise to sort out cibil report

hello, I  seek your valuable information  for the following  questions.

1) CIBIL IS  A PUBLIC BODY OR PRIVATE BODY?

2) THE INFORMATION AVAILABLE BY THE CIBIL MAY QUESTIONABLE OR NOT?

3)The information available about mine or some one else can I access thru RTI?

4) The information maintained by the Cibil is related with public, whether may I sue against them if I was suffered?

thanks

G M KUMAR