Thurstone's law of comparative judgment for paired comparison (Thurstone and Chave, 1929) provides an approach for estimating the perceived seriousness of crime typologies. Under this method, respondents are presented with a pair of crimes and asked to judge which one is more serious. From the proportion of times a crime is judged to be more serious than others, scores of seriousness can be constructed for the set of crimes. In Hong Kong, a telephone survey was conducted to determine the relative seriousness of crimes. Fifteen crime typologies were selected for the survey according to the following criteria: frequencies of occurrence and legal penalties. The weights of the 15 crimes constructed were then used to build up a time series of weighted crime index (WCI). The WCI performed differently from the unweighted crime index during the period 1976 to 1982. The validity of the weights has been tested, and the WCI was considered to be a better indicator of crime intensity. Murder, rape, drug offense, and robbery were perceived as the four most serious crimes by Hong Kong citizens. The four least serious crimes were theft, snatching, criminal damage, and possession of arms. 7 tables and 26 references