In this companion case to People v. Arnold, the Supreme Court held that the waiver policy adopted in Arnold applied equally to cases in which the defendant has entered a residential drug or alcohol treatment facility. The defendant was placed on probation and ordered to enter a residential treatment facility, and in order to qualify for placement in that facility she was required to waive all presentence custody credits as well as any future credits she would earn in the treatment facility. The court held that nothing in the agreement indicated that the waiver was limited in scope, and thus held that the waiver was knowing and intelligent and precluded the court from awarding those credits when the defendant was ultimately sentenced to prison.