Evaluating Shepard’s, KeyCite, and BCite for Case Validation Accuracy

Source: Paul Hellyer, Law Library Journal, Vol. 110 no. 4, Fall 2018

This study evaluates and compares how accurately three legal citators (Shepard’s, KeyCite, and BCite) identify negative treatment of case law, based on a review of 357 citing relationships that at least one citator labeled as negative. In this sample, Shepard’s and KeyCite missed or mislabeled about one-third of negative citing relationships, while BCite missed or mislabeled over two-thirds. The citators’ relative performance is less clear when examining the most serious citator errors, examples of which can be found in all three citators.