The age of consent normally is defined as the age at which a minor has the capacity to consent to sexual relations with another person. You are correct that the age of consent in Maryland is 16. However, under some circumstances--for example, if the 28 year-old has temporary custody of the child, or is related to her--having sex with a 16 year-old may still be criminal. Also, to say that it is legal for a 28 year-old to have sex with a 16 year-old does not mean that it's moral or healthy for the child.
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