Onus of Proof

‘Onus’ is simply the Latin word for ‘burden’. It is a concept relevant to Liability Insurance, where the onus, or burden, of proving negligence usually rests with the plaintiff.

There are certain circumstances, however, in which a prima facie (a Latin term which means ‘at first sight’ or ‘on first impression’) liability rests on one of the parties. Once it has been proven that an accident has occurred, for example, the onus is transferred to the defendant, to disprove his or her own negligence. See ‘Res Ipsa Loquitor’.