Del. Code tit. 16, § 3053F

The owner of a dog is liable in damages for any injury, death, or loss to person or property that is caused by such dog, unless the injury, death, or loss was caused to the body or property of a person who, at the time, was committing or attempting to commit a trespass or other criminal offense on the property of the owner, or was committing or attempting to commit a criminal offense against any person, or was teasing, tormenting, or abusing the dog.