As state above, Maryland is a statutory strict liability state where the attacking dog was at large, and where the dog owner cannot prove that he neither knew nor should have known that his dog was vicious or dangerous. The full text of Maryland Courts and Judicial Proceedings Code section 3-1901 is as follows:
(a) Rebuttable presumption of owner's knowledge. --
(1) In an action against an owner of a dog for damages for personal injury or death caused by the dog, evidence that the dog caused the personal injury or death creates a rebuttable presumption that the owner knew or should have known that the dog had vicious or dangerous propensities.
(2) Notwithstanding any other law or rule, in a jury trial, the judge may not rule as a matter of law that the presumption has been rebutted before the jury returns a verdict.
(b) Common law of liability for other than owner. -- In an action against a person other than an owner of a dog for damages for personal injury or death caused by the dog, the common law of liability relating to attacks by dogs against humans that existed on April 1, 2012, is retained as to the person without regard to the breed or heritage of the dog.
(c) Liability of owner. -- The owner of a dog is liable for any injury, death, or loss to person or property that is caused by the dog, while the dog is running at large, unless the injury, death, or loss was caused to the body or property of a person who was:
(1) Committing or attempting to commit a trespass or other criminal offense on the property of the owner;
(2) Committing or attempting to commit a criminal offense against any person; or
(3) Teasing, tormenting, abusing, or provoking the dog.
(d) Limitation of effect of section. -- This section does not affect:
(1) Any other common law or statutory cause of action; or
(2) Any other common law or statutory defense or immunity.