You are wrong,judges need not read about the case at all. It is the duty of the lawyers and the public prosecuters. When the modern juduciary took it's shape in England hundreds of years back the precedence was established. The first judge sentenced a criminal for a particular crime,the next day he and his hench men had the audacity to attack the judge in his home. When the case came to the court the judge did not punish the criminals because the public prosecuter and the lawyer did't do a good job.Public did't understand why the judge did't punish them. The judge see how the case is produced in front of him and the public,he is not to find out the truth,but to render justice. It is the lawyers who toil for sleepless nights to find out any loopholes or discrepencies in the case. On the day of writing the judgement only the Judge has to refer to find out how much punishment and what punishment to be given. It is notorious that our judicial system is slow. We have judges who give blank arrest warrants for a few thousand Rs,on which the police or anybody can write anybody's name even the name of the President of India or the Chief Justice.
