Complex sentence: Under these systems, sentencing judge does not sentence convict into sex offender registry and "cannot" usually use judicial discretion to forgo registration requirement, even if he thinks the registration would be unreasonable taking account mitigating factors pertaining to individual cases.
Split into simpler sentences: Under these systems, sentencing judge does not sentence convict into sex offender registry. Therefore, sentencing judge "cannot" usually use judicial discretion and forgo registration requirement, even if he thinks the registration would be unreasonable taking account possible mitigating factors pertaining to individual cases.