What is Bloody Hand?

Legal Definition
Under the old English forest laws, bloody hand was one of the four kinds of trespasses in the royal forest, by which the offender, being apprehended and found with his hands or other body part stained with blood, is judged to have killed the deer, even though he was not found hunting or chasing.
-- Wikipedia
Legal Definition
In forest law. The having the hands or other parts bloody, which, in a person caught trespassing in the forest against venison, was one of the four kinds of circumstantial evidence of his having killed deer, although he was not found in the act of chasing or hunting. Manwood.
-- Black's Law Dictionary
Legal Definition
A hand stained with deer’s blood, evidence of trespass.
-- Ballentine's Law Dictionary