> “You cannot create a back door that only the good guys can go through,”
Alright, technical argument here. This is false and tech talking heads are spreading this lie for ideological reasons.
You don't need to backdoor the protocol, just the specific targeted client.
Now, if Signal said this is unfair because competitors won't also backdoor their app then I am with them. What the UK should probably have done is to force phone makers as opposed to app makers to facilitate a backdoor.
Signal can scan messages before encryption and report to the authorities just fine. Whatever the UK government desires, Signal should accept it as the will of the UK people, especially given that politicians' stance on this has been public and endured election cycles.
I do get their stance, people will stop using them if they cave in and the UK gov should know that as well.
I don't know UK law but dragnet surveillance is illegal in the US but targeted warrantful requests to backdoor apps is lawful.