What is a 'but for' test used for in malpractice claims?

The 'but for' test is primarily used in malpractice claims to establish causation of injury. In the context of legal malpractice, the test examines whether the harm the client suffered would have occurred 'but for' the lawyer's negligence or error. It is a way of determining whether the lawyer's actions were a necessary condition for the harm to happen. If the client can show that they would not have experienced the injury had the lawyer acted competently, then this test helps to establish a direct link between the lawyer’s conduct and the client’s damages. This causal connection is crucial in malpractice claims because plaintiffs need to prove not only that the lawyer made a mistake, but also that this mistake was the reason for the client's negative outcome.