Attempts by two states to weaken the encryption available on smartphones could be blocked by a federal law. The measure would stop laws which could mean a major redesign of many high-profile handsets

As we’ve previously covered, state legislators in New York and California are both considering suspiciously similarly worded bills on the matter. Both would make it an offense to sell a phone which had encryption that the manufacturer is not capable of decrypting.

That would include several iPhone and Android models which have been intentionally designed so that even if a court order told the manufacturer to decrypt files on a suspect’s phone, they would be unable to do so. In both cases the politicians proposing the bill have argued that the laws are needed to stop criminals being able to communicate in total secrecy and that this outweighs privacy rights.

If passed, the measures would kill demand among retailers in the states for many current models of phones. That would leave manufacturers having to either make special models for those states, modify the encryption for all handsets, or abandon almost a fifth of the US market.

Both state bills are in very preliminary stages with substantial doubt over whether they’ll ever become law. However, two members of the national House of Representatives aren’t taking any chances. Republican Blake Farenthold and Democrat Ted Lieu have proposed the painfully titled “Ensuring National Constitutional Rights for Your Private Telecommunications Act” (aka ENCRYPT.) It’s a federal law that would block the proposed laws and any other state bills which tried to achieve the same goal.

Lieu told Ars Technica that there’s a simple principle behind the idea: “You cannot have a backdoor key for the FBI. Either hackers will find that key or the FBI will let it get stolen. “