§ 923 Defendant discharged on acquittal - Variance resulting in acquittal may authorize new charges.

If you're found not guilty at trial, you get to go free right away, as long as you're not being held for some other legal reason. This happens automatically once the judge enters the acquittal.

There's one exception to this. Sometimes a person is found not guilty because the evidence presented at trial didn't quite match what the charging paperwork said (this is called a "variance"). If the problem is something that could be fixed by filing new, corrected charges, the court can keep holding the person instead of letting them go. This gives prosecutors a chance to file new charges that properly match the evidence.

So the difference comes down to why someone was acquitted. If it's a straightforward not guilty verdict, the person walks free. But if the not guilty verdict happened because of a paperwork or technical mismatch that could be corrected, the court can hold the person while new charges are prepared.