My question involves criminal law for the state of:

If someone was on probation for a violent crime and one of their stipulations was no drug or alcohol use, what would happen if they abused both drugs & alcohol, but were never caught while on probation? If the proof randomly surfaced through accurately archived video after successfully completing probation....say they were on probation from 2005-2010, and it came to their attention NOW that the convicted person had in fact been actively using during the time they were on "papers" also same with leaving the state...what if they went to another state when told they couldn't leave a certain jurisdiction and a judge was watching another states news and found out that person had been in another state (again, after probation is over)