Mechanisms for evaluating an evidential statement in a corpus of evidence are provided. A first evidential statement for which corroboration is sought is received and a corpus of evidence data is processed to determine a measure of corroboration of the first evidential statement by other evidence data in the corpus of evidence data. An indication of trustworthiness of the first evidential statement is generated based on the measure of corroboration of the first evidential statement by the other evidence data in the corpus of evidence data. A representation of the indication of the trustworthiness of the first evidential statement is output in association with the first evidential statement.