Nemo Judex in Causa Sua

Nemo judex in causa sua, also known as the rule against bias, is one of the two cardinal principles of natural justice in Indian law. It ensures that justice is not only done but is manifestly seen to be done. The principle requires that the adjudicating authority must be impartial and free from any bias.

Under Indian law, bias can be of several types: pecuniary bias (financial interest in the outcome), personal bias (relationship with parties), subject matter bias (preconceived notions about the issue), and departmental bias (official interest in the outcome). The Supreme Court has held that even a reasonable likelihood or apprehension of bias is sufficient to disqualify a judge or decision-maker.

The principle applies to all judicial, quasi-judicial, and administrative proceedings. An order passed by a biased authority is voidable and can be set aside. The test is whether a reasonable person, aware of the relevant facts, would reasonably apprehend bias. Indian courts have extended this principle to include 'institutional bias' and 'official bias' in administrative matters.