It's a good rule of thumb to store packaged deer meat in the freezer for up to 9-12 months. With that said, I have eaten deer meat that was 2 years old before and it was still good. Be sure to prepare and seal the meat properly before freezing and make sure it stays frozen until ready to be eaten. This will help it stay good longer. If the deer meat is over a year old and the color and smell are off, I'd say throw it to the dogs!