If you are eligible for the Maryland Medicaid program or the Maryland Children's Health Insurance Program (MCHP), expect to see a letter from the government informing you of that. How do they know? They will use your tax records, of course. Sure, you thought that information was only used to determine how much you owe the government in taxes. You may have thought that since the Maryland tax forms explicitly state:
The Tax-General Article of the Annotated Code of Maryland authorizes the Revenue Administration Division to request information on tax returns to administer the income tax laws of Maryland, including determination and collection of correct taxes.
Perhaps they forgot to mention that the Revenue Administration Division can request tax return information to administer state welfare programs. I guess that was just an oversight.