If a person was arrested for a DUI and they were already on probation for a different type of charge would they still have to serve the time that was given to them for their original charge?

When a person picks up a new charge while they are on probation for another criminal offense, then they are subject to a penalty for each offense.  The prosecutor can ask that each sentence associated with each offense be served separately or be stacked.  However, through the plea bargaining process, many sentences are ordered to run concurrent--- which means that while a defendant is serving a sentence for one charge they will be getting credit towards their sentence on the original charge.  If a defendant and the prosecutor cannot agree on how a sentence will be served, then the judge has the discretion to order stacked sentenced when there is a probation violation per the Hawaii Penal Code.