Yes, but this would mean you were storing the unhashed passwords in the DB. When your DB is compromised, everyone's password is exposed, likely along with their email. In this world of frequent password reuse, that is pretty much game over.
... WHERE user.hashed_password = hash(input) OR user.hashed_password = input
This solves the problem of passwords being stored in plaintext (indeed a problem with frequent password reuse) while apparently getting around this silly French law.
Sure if the database is compromised anyone will be able to login to anyone's account, but the database is compromised so who cares?
Also if you wanted to make it secure you could restrict hash passwords to work only from certain IP addresses so you either have to be using a company internal machine or say the IP addresses from a police station.
He was referring to my rebuttal, which was initially downvoted for some reason.