WordNet (r) 3.0 (2006):

case in point
    n 1: an example that is used to justify similar occurrences at a
         later time [syn: precedent, case in point]

Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "case in point":
   case, citation, cross reference, demonstration, emblem, example,
   exemplar, exemplification, explanation, exponent, illustration,
   instance, item, object lesson, particular, quotation, reference,
   relevant instance, representative, symbol, type, typical example