When jello shots are made correctly, they will not freeze. A jello shot is an alcoholic beverage that consists of distilled liquor mixed into a gelatin dessert and chilled.
The alcohol that is used to make the jello shots freezes at a lower freezing point than water. Most domestic freezers won't get this cold. If the jello shots are placed in the freezer, the liquid can start to crystallize, the consistency of the liquid will begin to change, and the taste will not be the same.
Popular choices to use in jello shots include rum, tequila and vodka.