[lazide]

'Blameless postmortem' requires people are able to discuss things without being blamed.

If they are (or are likely to be) being criminally prosecuted, being completely candid would require they'd have to be idiots or so clearly innocent of wrongdoing even the most cynical lawyer thinks it will be fine.

Even if someone tries to falsify evidence or frame their client.

Which everything being easy and fine is not very likely, frankly.

Especially when a bunch of pissed off commuters and taxpayers are pressuring politicans, families are looking for compensation for dead relatives, and you're front page news globally - with damages running in the hundreds of millions at a minimum.