(not a lawyer or french) but generally yes - it's your responsibility to give the password to the police, forgetting it would be equivalent to forgetting to pay at a store or forgetting to put on a seatbelt while driving - it may be accidental but still illegal. I don't know of any laws where you can legitimately claim ignorance
That is a looong shot! The responsibility for my passwords is mine and sole mine!
Other thing is being negligent with password security, and a breach leading to damage of property of life... but forgetting a password is not a crime! never.
Is this your belief of the law as it stands or how you feel the law should be?
"forgetting a password is not a crime" is a statement of fact, and the only thing required to make it a crime is a law saying it is a crime. "Crime" is not some universal absolute, what is and is not can obviously change drastically over time.
Yeah I'm not saying this is what I think it correct - it's just how the law seems like it works. Ultimately you'd have to convince a jury and I don't think most people would believe "I just happened to forget it when the police asked for it". In the US you aren't required to give the police your passcode, but they do have a legal right to use your face/fingerprints without your permission, so they can freely search if there's only a biometric lock but not a passcode. Very weird but that's how the laws were written