It seems so simple but perhaps it is not. Conditions of probation at some level need to be reasonably related to the defendant and/or the offense. So the decision of the Massachusetts Supreme Judicial  Court may not be shocking to anyone (but the defendant). The Massachusetts Supreme Judicial Court Massachusetts v. Eldred, No. SJC–12279 (Mass. July 16, 2018) (available here). The opinion starts this way:

Following a probation violation hearing, a judge in the District Court found that the defendant, Julie A. Eldred, had tested positive for fentanyl, in violation of a condition of her probation requiring her to abstain from using illegal drugs. The judge ordered that the conditions of her probation be modified to require her to submit to inpatient treatment for drug addiction. The defendant appeals from that finding and disposition.  The judge also reported a question drafted by the defendant concerning whether the imposition of a “drug free” condition of probation, such as appeared in the original terms of defendant’s probation, is permissible for an individual who is addicted to drugs and whether that person can be subject to probation violation proceedings for subsequently testing positive for illegal drugs.

We conclude that, in appropriate circumstances, a judge may order a defendant who is addicted to drugs to remain drug free as a condition of probation, and that a defendant may be found to be in violation of his or her probation by subsequently testing positive for an illegal drug. Accordingly, we affirm the finding that the defendant violated her probation and the order requiring her to submit to inpatient treatment for her addiction.