This happens in the episode where Fred breaks Lamant's porclain collection, hides it and claims guys broke in, beat him up and stole it. At the beginning when fred is vacuuming the rug and knocks over the table with the porclain, you can see one of the legs is on a hinge and was designed to fall over quite easily. In fact you can see the leg continue to wiggle back and forth while Fred panics.