noun
first offense
Refers to the first criminal act committed by a person. Often used in legal or formal contexts, contrasting with 再犯 (repeat offense).
See also: 再犯
彼は初犯だったので、執行猶予がついた。
Since it was his first offense, he received a suspended sentence.
noun
first-time offender
Refers to a person who has committed a crime for the first time. The term 初犯者 is also common.
See also: 初犯者
初犯の場合は、更生の機会が与えられることが多い。
First-time offenders are often given a chance for rehabilitation.