Legal Question in Constitutional Law in Maryland

Re: Can Civil charges be filed if Defendant was acquitted in criminal case?

Yes. This is what happened in the O.J. Simpson case here in Los Angeles, but he is just the most famous example.

The constitutional bar against Double Jeopardy only applied to criminal proceedings. I will spare you a detailed analysis of when it does and does not apply, but it is entiely irrelevant to civil claims.

Bear in mind that an acquital does not mean that the defendant is innocent. Instead, it means only that the jury was not persuaded of his guilt beyond a reasonable doubt. The jury may have believed he was guilty but had enough doubt to be unwilling to convict. In a civil case, the plaintiff does not need to prove guilt beyond a reasonable doubt, so it is entirely consistent for a criminal jury to acquit a defendant and for a subsequent civil jury to rule against him.

In some very rare instances, a criminal court will issue a finding of actual innocence. Such a finding might bar civil damages in some jurisdictions, but I don't know whether it would in your state. Besides, it almost certainly did not happen in the case you have in mind.