In addition to what Mr. Pierce-Jones wrote, whether or not your boyfriend serves time will be up to the judge. If the judge sets new bonds (usually double or more than the original) and he pays them, then he will be in the free world while fighting the new assault case. The State may try to prove up the new case in a probation revocation hearing. If the Judge finds by a preponderance of the evidence that he committed a new law violation, the judge can sentence him up to 180 days in jail on the POM (assuming it is a class B misdemeanor). On the other hand, if he is found guilty or or pleads guilty to the assault case, he could be sentenced up to 1 year in jail. As a general rule, when a person violates probation, it is usually better to work out a plea deal with the prosecutor, but of course it all depends on the facts, circumstances and the judge, so it is important to hire a local attorney who is on good terms with the judge and the prosecutors.
Translation: assault causing bodily injury (failure to appear) and possession of marijuana (motion to revoke probation).
Some basic concepts may help in understanding this situation. When a person is arrested and posts bond, the case may or may not be filed in the trial court (or for a felony, indicted). The person who was arrested is expected to come back to court when and if the case is filed in the trial court. If the person does not come back to court, that is a "failure to appear", and in most cases is also a new charge.
On a probation revocation, so long as a motion to revoke is filed and a warrant issued before the probation expires, the revocation case stays active even after the probation term expires.
Those are just some basic ideas. There is not enough information given in your question to get more specific. But, at this point if you boyfriend does not have an attorney, it's time he gets one.
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