Because of its complex nature, surgical pathology diagnosis has an appreciable degree of fallibility and is increasingly subject to legal scrutiny. In litigation, the first practical step is to explain why and how this adversity could happen, and the second is the question of apportionment of responsibility and its legal consequences. As pathologists, we have to provide a methodology of investigation allowing a clear distinction between reasonable and unacceptable pathology practice without the twist of hindsight. For that we need to examine the different steps from test ordering to the final report. The most critical aspect of the enquiry is the act of diagnosis itself. What can reasonably be expected and what precautions have normally to be taken? Experts are often requested to re-examine the slides. For that we need a well-devised protocol enabling blinded review. Tort law has two important interconnected goals: compensation for damages and prevention of the same slip ever being made again. We can only properly learn from our mistakes if we carry out an unbiased investigation. Poor normative judgement of diagnostic failures will back-fire on the profession.