The Maryland Code states as follows:
(a) Subject to the provisions of §§ 6–202 and 6–203 of this subtitle and unless otherwise provided by law, a civil action shall be brought in a county where the defendant resides, carries on a regular business, is employed, or habitually engages in a vocation. In addition,a corporation also may be sued where it maintains its principal offices in the State.
(b) If there is more than one defendant, and there is no single venue applicable to all defendants, under subsection (a) of this section, all may be sued in a county in which any one of them could be sued, or in the county where the cause of action arose.
As you can see, you need to sue in the county where the defendant lives or is employed, etc. You cannot sue in Baltimore County if the defendant has no connection to Baltimore County. The fact that the breach and harassment occurred there would only be relevant if there is more than one defendant, and they do not all live or work in the same county. And the fact that you reside in Baltimore County is not a factor in determining venue.
In any event, once you determine the correct county, your Complaint would have a statement like this:
"This Court has jurisdiction over this matter pursuant to MD Code, Courts and Judicial Proceedings, § 6-201."
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