Indian Evidence Act, 1872
[54. Previous bad character not relevant, except in reply.–– In criminal proceedings, the fact that the accused person has a bad character, is irrelevant, unless evidence has been given that he has a good character, in which case it becomes relevant. Explanation 1.––This section does not apply to cases in which the bad character of any person is itself a fact in issue. Explanation 2. ––A previous conviction is relevant as evidence of bad character.]