The probability of causation (PC) is often used in liability assessments. In a legal context, for example, where a patient suffered the side effect after taking a medication and sued the pharmaceutical company as a result, the value of the PC can be used to measure how likely it is that the side effect can be attributed to the taking of the medication, i.e., how likely it is that the patient will win the case. Beyond the issue of legal disputes, the PC plays an equally large role when one wants to go about explaining causal relationships between events that have already occurred in other areas. This article first reviews the definitions and bounds for the probability of causality under binary outcomes, then generalizes them to ordinal outcomes and shows that taking into account additional mediator variable information in a complete mediation analysis yields an improved bound compared to the simple case where only exposure and outcome variables are considered.