I had a beemer a long time ago and the doors were reputed to auto unlock if you were in an accident, but no auto lock in though.
Don't know why Honda have not incorporated auto lock on UK cars as several other makers have done so, as have Honda on the US model (according to the US handbook). it's obviously not a UK/EU law preventing its incorporation. Or the walk away locking that's apparently on the US model that would be great.
Just been and checked my 10G.
When you lock the doors with the driver's door handle tab, all doors lock. The passenger and driver can unlock theirs by pulling the door handle, but the rear doors won't open (child protection?).
When you lock the doors with the driver's armrest button or the key fob button, all doors lock. The passenger and driver can unlock theirs by pulling the door handle, but the rear doors won't open (child protection?).
The only way to unlock the rear doors is to use the unlock button on the driver's armrest or use the key fob unlock button.
So I can't see what the problem is with auto locking as fitted to many cars these days and the US Civic.
The only proviso is, that in an accident, if the doors have been locked by the driver, the rear doors can't be opened from the inside and auto locking would make no difference in this scenario.
As I said before, I had a BMW that (reputedly) auto unlocked the doors in an accident, presumably linked to the air bag deployment detection. It didn't have auto locking though.
If not already incorporated into the Civic, it damn well should be.