It is an odd take on private property law that allows armed intruders to enter at will and fire away whether the landowners like it or not.

But such is the situation in some states — Massachusetts among them as Westport residents have just learned.

Voters there at last spring’s town meeting approved by a healthy margin a measure requiring hunters to get annual written permission from property owners before venturing onto private land. It seemed like common sense — so obvious even as to scarcely need spelling out.

Not so fast, the state’s attorney general wrote last week. Towns can’t set hunting rules that conflict with state Fish and Game.

Townspeople should forget what they thought they understood about the notion of private property and trespassing, the letter suggests. The AG pointed to a clause in the state code that “presume(s) that private land is open to hunting and trapping” unless that land is conspicuously posted with no-hunting signs.

It is a startling legal ‘presumption’ that any stranger, armed or not, can wander about another’s property without permission. Just as offensive is the idea that responsibility for respecting property lines rests with the property owner, not the trespasser.

Some who testified last spring said that posting no-hunting signs every 50 feet around a boundary as required is a costly waste of considerable effort. Hunters merely rip signs down, they say, then enter at will.

Homeowners said they are frightened to walk about their own land, repulsed by carcass parts left behind, frustrated by vandalism and worried about lawsuits.

Not all hunters behave badly, of course, but emotional testimony suggested that the problem is real and one that state Fish and Game needs to confront, despite its evident desire to please those who buy hunting licenses.

Some 22 states (Rhode Island recently among them) require that deer hunters on private land carry written permission.

Massachusetts should be among those states. Private property rights should trump hunting rights every time.