Juvenile capability to waive their rights to counsel and to silence was evaluated in terms of (1) intellectual comprehension of rights and (2) understanding of significance of rights within the legal system. Evaluation criteria employed included asking juveniles to (1) paraphrase the rights, (2) define key words, (3) identify sentences with similar meanings, and (4) react to four drawings accompanied by a brief story and depicting interrogation scenes. The data were derived from a random sample of 491 felony referrals to the St. Louis County, Mo., juvenile Court in 1974 and 1975. The statistical analysis of the results indicates that, as a class, juveniles of ages 14 and below are incapable of waiving their rights. Juveniles of ages 15 and 16 who have IQ scores of 80 or below lack the requisite competence to waive rights to silence and counsel. As a class, however, this age group demonstrates a level of understanding and perception similar to that of 17 to 21-year-old adults for whom the competence to waive rights is presumed in law. Race is a relevant variable for consideration, since more black juveniles performed in the lower IQ range and since blacks in the low socioeconomic class may have greater difficulty translating the Miranda warnings than whites of the same class. To remedy the situation, the study suggests providing legal blanket exclusion of confessions or providing for automatic legal counsel for all juveniles 14 years and below. Another solution would be to have judges use the study's research results in weighing individual juveniles' competence to waive rights. The study includes detailed demographic information on the sample population, numerous statistical charts, all evaluation tools, and bibliography of about 120 citations.