What is the ruling on one who dies as a result of falling into a hole in a private park, knowing that the hole is not on a public thoroughfare?

Among the jurisprudential maxims is: "Permissibility by Sharee'ah negates liability." Its meaning is that whoever does what is permissible for him by Sharee'ah, and harm results from it, he is not liable for the loss arising therefrom. So, if a person digs a well on his property and another's animal falls into it and perishes, the digger of the well is not liable for anything. However, if he digs it in a public road without permission, or on someone else's property, or on jointly owned property, then liability is incumbent. Based on this, if the park owner did not dig the hole to harm anyone and took safety precautions, then liability is not incumbent upon him.