2013, but are these really peter's bones? >> once the vatican has made a statement like, "we think these are the bones of peter," no one's ever going to have the freedom to return to them in order to disprove that claim. >> the vatican believes that further scientific investigation is unnecessary, because these remains have been authenticated. >> but ever since the bones were discovered, margherita guarducci's work has come under intense criticism. >> there are a couple of problems with guarducci's claims. one is the graffiti. so there's this graffiti on a wall. it's truncated, which means it's shortened. we don't know how it finishes. guarducci says that it reads "peter is here," but other scholars have said, "well, it could actually say that peter is missing." >> i think part of margherita guarducci's story was that she wanted very much to find peter,