(c) Prohibited.-
(3) (i) This paragraph applies in Anne Arundel County, Baltimore County, Caroline County, Cecil County, Harford County, Kent County, Montgomery County, Prince George's County, St. Mary's County, Talbot County, Washington County, and Worcester County.
(ii) A minor may not carry a dangerous weapon between 1 hour after sunset and 1 hour before sunrise, whether concealed or not, except while:
1. on a bona fide hunting trip; or
2. engaged in or on the way to or returning from a bona fide trap shoot, sport shooting event, or any organized civic or military activity.
(d) Penalties.-
(1) A person who violates this section is guilty of a misdemeanor and on conviction is subject to imprisonment not exceeding 3 years or a fine not exceeding $1,000 or both.
(2) For a person convicted under subsection (c)(1) or (2) of this section, if it appears from the evidence that the weapon was carried, concealed or openly, with the deliberate purpose of injuring or killing another, the court shall impose the highest sentence of imprisonment prescribed.
[An. Code 1957, art. 27, § 36; 2002, ch. 26, § 2; ch. 213, § 6; ch. 571, § 1; 2003, ch. 17; ch. 21, § 1.]
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from Bernard Levine's Knife Laws site.
There are other sites too, if you really want to know you should investigate further.
For example, who is a "minor" in Maryland? (Different states have different ages, as far as I know.)