Technology industry experts including inventors of modern cryptography, told a federal court today that forcing Apple to write and sign computer code disabling crucial iPhone security features that protect users violates the company’s free speech rights. On the other hand, several police groups filed briefs in support of federal authorities who are seeking Apple's help in hacking an encrypted iPhone used by Syed Farook, one of the San Bernardino mass shooters.

The briefs come in advance of a March 22 hearing in which Apple is asking U.S. Magistrate Sheri Pym to reverse an order requiring Apple to create a software program that over-rides iPhone security features, so authorities can try to unlock the encryption by guessing the phone's passcode.

Among those backing Apple in the dispute are some of its biggest competitors, including Google, Microsoft and Facebook. A group of 17 smaller tech firms, including Twitter, LinkedIn, Airbnb and Reddit submitted a separate joint filing.

"The court order is akin to the government dictating a letter endorsing backdoors and forcing Apple to sign its forgery-proof name at the bottom," said Electronic Frontier Foundation (EFF) Civil Liberties Director David Greene. "In our democracy, no one - not technology companies, coders, or average citizens - can be forced to write an article, carry a sign, post an update on Facebook or write and sign computer code that communicates or endorses a government idea that they don’t agree with. What the FBI asked the court to do violates free speech rights and puts the security and privacy of millions of people at risk. We are asking the court to throw out this dangerous and unconstitutional order."

Telecommunications giant AT&T also filed a brief arguing that current law doesn't support the government's demand. AT&T urged the magistrate to rescind her order and let Congress address the issue.

The Computer and Communications Industry Association also said its members invest heavily in technical measures to protect customers' information against theft by criminals and hackers backed for foreign states.

CCIA members include Google, Facebook, Amazon and Microsoft - but not Apple.