The study explored whether previous findings concerning juror construal in insanity cases were due simply to verdict justification effects; whether GBMI instructions directly influence the construal process or only the verdict selection process; and whether a between-instructions comparison of construals clarifies the nature of the shifting in verdicts that accompanies the GBMI verdict. These results refined previous research by showing that verdict distributions were unaltered by the order of construal measurement and that levels of construal ratings and the close association between construals and verdicts did not differ across orders of measurement. The mechanism of the GBMI effect on individual decision making appears to lie in some process other than a direct influence upon responsibility construal dimensions. However, the verdict selection process is clearly affected by the availability of the GBMI option, even in cases involving highly psychotic defendants. The between-instruction comparisons of construals indicated that insanity and guilty verdicts reached in response to GBMI instructions corresponded to attributionally more extreme judgments. 2 tables and 26 references