Presumably you are an adult of legal age, but it's hard to tell as people misuse terms like prison to refer to county jail etcetera. The issue is whether or not the court ordered a no alcohol clause/term/condition? Generally, probation terms must have a nexus to the offense. However, sometimes in some jurisdictions a court may order testing, to include alcohol, if a non-drug related crime was committed, while the offender was under the influence or has a history of committing propertry crimes to "feed his/her habit."
Need more info. BTW, ordinarily, probationers are provided with copies of court/probation orders with all the applicable terms. What does yours say?

