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Imagine not being able to buy an iPhone in your state because the device's data is protected by encryption. A couple of Congressmen are trying to make sure that can't happen.

The Encrypt Act of 2016, short for Ensuring National Constitutional Rights of Your Private Telecommunications Act, would deny states the power to block the sale of encrypted smartphones or to require that manufacturers equip their phones with a back door to access private data. The bill is set to be introduced Wednesday by Rep. Ted Lieu, a Democrat from California, and Rep. Blake Farenthold, a Texas Republican.

Encryption is built into Apple's iPhone, Android phones and other smartphones to make your personal data safe from prying eyes. An encryption key is needed to decrypt the data, which the smartphone manufacturers do not possess.

The bill comes as lawmakers and Silicon Valley tech giants are trying to figure out how to compromise on device encryption. Some law enforcement officials, including FBI Director James Comey, have spoken out against the increased use of encryption on phones. Data stored on phones, they argue, could be useful in investigations against ordinary criminals as well as suspected terrorists.

The bill is a reaction to proposals from New York and California, which would ban encrypted smartphones in their respective states and fine manufacturers of such phones. Assuming those proposals were turned into law, smartphone companies would be required to enable decryption of data on phones made after 2017.

Trying to enforce smartphone encryption on a state level would be a confusing and difficult process, according to Lieu.

"Having 50 states with 50 different encryption back doors standards or bans is a recipe for disaster for American privacy and competitiveness," Lieu said in an email. "This conversation belongs at the national level, where we can find a solution that protects the privacy rights of Americans and does not create additional vulnerabilities. The ENCRYPT Act makes sure that this conversation happens in a place that does not disrupt interstate commerce."

Companies such as Apple have been accused of equipping their phones with back doors, openings coded into software that let law enforcement bypass security measures. Apple CEO Tim Cook has rebutted those claims and argued against the use of back doors. Last month, Cook called on the Obama administration to issue a statement defending the use of unbreakable encryption.

The Encrypt Act covers any computer hardware, computer software, electronic device or online service.