The Act to Amend the Criminal Code in relation to sexual offenses and other offenses against the person became effective in January 1983. This act produced significant changes in both substantive and evidentiary law concerning sexual offenses. Crimes of rape, attempted rape, sexual intercourse with the feeble-minded, and indecent assault were repealed. In their place, the new law established three sexual assault levels: (1) sexual assault; (2) sexual assault with a weapon, threat to a third party, or causing bodily harm; and (3) aggravated sexual assault. The new law also changed rules of evidence applicable to sexual offenses. Rape victims had been expected to report the crime immediately; this requirement was repealed. In addition, courts could not previously convict an accused based solely on victim testimony; the new law removed the requirement for corroboration. The new law also narrowly restricted the circumstances under which the court could hear evidence of a victim's past sexual history and prohibited the introduction of evidence about a victim's sexual reputation. A total of 240 court decisions made after the law's implementation are reviewed and interpreted with respect to the following: nature of the sexual assault offense (use of force, victim's lack of resistance, issue of consent, and cases involving husbands and wives); mental state of the accused (intent to commit the crime, accused's belief in consent, and burden of proof regarding consent); evidentiary matters related to sexual assault trials (corroboration and evidence admissibility); and procedural issues (charging patterns, level of detail required in sexual assault charges, ban on publication or broadcast of information that could identify the complainant, and allowing third parties to present arguments in court). Appendixes contain sections of the Criminal Code pertaining to sexual assault, a table of reported cases, research reports on sexual assault, and case selection procedures.