How indeed? If a specimen was a fraud, we shouldn't find any more of them. We have lots of australopithecine finds. Therefore, the claims of fakery aren't looking too good.
Well, now, that's only because the Darwin CentralTM faketory in The Galapagos was closed years ago in a cost cutting frenzy. (As a senior operative you'll remember that's the same year the bourbon/beer allotment was slashed to a mere case/keg a week.) The afarensis dies have since been moved to the Kuala Lampur frauduction facilities and "new" members of "Lucy's" family can now be assembled and salted at will or need.