A more thorough explanation:

A stable stand is a term used in forest law to describe a person who is found standing in a forest with a bow bent, ready to shoot a deer, or near a tree with greyhounds on a leash and ready to release them. This is considered presumptive evidence of an intent to steal the Crown's deer.

For example, if a person is found in a forest with a bow in their hand and a deer in sight, it is assumed that they intend to shoot the deer and steal it. Similarly, if a person is found with greyhounds on a leash near a tree where deer are known to gather, it is assumed that they intend to release the dogs to chase and catch the deer.

The concept of a stable stand was used in forest law to help prevent poaching and protect the Crown's deer. It was a way to catch people who were attempting to steal deer without having to catch them in the act.