Which was a big deal precisely because the BBC is indeed not allowed to lie in public statements. Note, however, that this claim about Eccleston and Moffat is not from a BBC spokesperson in an institutional context, but from an "official source," i.e., whoever has been delegated to deliver the current PR line to Digital Spy. (An official spokesperson certainly wouldn't have called them "Chris" and "Steven.") That doesn't mean it's not true, but it's also not quite as authoritative as some people have assumed.