this is what MD tax return instructions say
WHO IS A RESIDENT?
You are a resident of Maryland if:
a. Your permanent home is or was (?) in Maryland (the law refers to this as your domicile). - was I think must refer to the current tax year otherwise anyone who ever had a permanent home in MD would always be considered a resident
OR
b. Your permanent home is outside of Maryland, but you maintained a place of abode (a place to live) in Maryland for more
than six months of the tax year. If this applies to you and you were physically present in the state for 183 days or more,
you must file a full-year resident return.
the issue that MD could raise is the use of your father's address especially if you stay there. It could argue you are maintaining a place of abode in the state that coupled with your driver's license if it uses your father's address.
the fact that you use MD based banks and financial institutions does not create domicile key in determining residency. however, were you to own say rental property in MD, then even if you are not a resident you would be responsible to file a non-resident return to report the rental activity.
