National animal activists have complained about the way Northumbria Police have handled cruelty allegations.
Anti-snare campaigner John Gill says he discovered a dead deer trapped in a snare as he walked through the Softley Woods on The Featherstone Estate, near Haltwhistle, Northumberland.
Self-locking snares are banned but the free-running type found by Mr Gill, which relax slightly, are legal.
Mr Gill, who admits to having removed more than 40 snares from the private estate, said: “I telephoned the police and an officer came and took away the snare but not the deer.
“This deer was just left to die.”
Mr Gill, 54, of Castleside, Consett, Co Durham, who has done four stretches in jail for offences including destroying snares and not paying fines when found guilty, added: “A policeman later contacted me and said the matter would not be taken further because he said the gamekeeper would say that the deer had been accidentally caught.”
Simon Wild of the National Anti-Snaring Campaign, who has written to the Northumbria Force about the case, said: “We feel there is a series of flaws in the way Northumbria Police have dealt with this matter.”
A Northumbria Police spokesman said: “The letter is being studied. We will reply in due course.”
A spokesman for the Featherstone Estate claimed: “It seems likely a deer carcass has been brought to the scene and planted.”