(Reuters) – Apple Inc on Thursday struck back in court against a U.S. government request to unlock an encrypted iPhone belonging to one of the San Bernardino shooters, arguing such a move would violate its free speech rights and require the company to devote significant resources to comply.

The U.S. Federal Bureau of Investigation is seeking Apple’s help to access shooter Rizwan Farook’s iPhone by disabling some of its passcode protections.

Apple argued in its brief that software was a form of protected speech, and thus the Justice Department’s demand violated the constitution.

“The government’s request here creates an unprecedented burden on Apple and violates Apple’s First Amendment rights against compelled speech,” it said.

Apple also argued that the court was over-stepping its jurisdiction, noting that Congress had rejected legislation that would have required companies to do the things the government is asking Apple to do in this case.

Apple said the court order, if upheld, could leave individuals and business vulnerable to an unlimited array of government directives.

“Under the same legal theories advocated by the government here, the government could argue that it should be permitted to force citizens to do all manner of things ‘necessary’ to assist it in enforcing the laws,” Apple said. It gave examples, “like compelling a pharmaceutical company against its will to produce drugs needed to carry out a lethal injection in furtherance of a lawfully issued death warrant or requiring a journalist to plant a false story in order to help lure out a fugitive.”

Apple’s resistance has intensified a national debate about whether the government should have technological access, or a “back door” to get into privately owned phones. The Justice Department has argued that Apple has no legal basis to refuse its help.

Some of the largest tech companies appear to be lining up behind Apple. Google and Facebook will both file briefs supporting the iPhone maker, said several sources familiar with the matter who were not authorized to speak publicly about it. Microsoft will file a friend-of the-court brief as well, company President Brad Smith said in congressional testimony Thursday. Twitter also said it will sign a brief in support of Apple.

Apple laid out in its brief the resources it believes would be necessary to comply with the government’s request, saying it would likely require a team of up to 10 Apple engineers and employees for as long as four weeks.

Complying with the request would also likely lead to “hundreds” of more demands from law enforcement, Apple said.

“Responding to these demands would effectively require Apple to create full-time positions in a new ‘hacking’ department to service government requests,” the company said in the filing.

“Apple would need to hire people whose sole function would be to assist with processing and effectuating such orders,” wrote Lisa Olle, an Apple lawyer and manager of privacy and law enforcement compliance. “These people would have no other necessary business or operations function at Apple” and would be charged with crafting what Apple referred to as “GovtOS.”

Government officials have rejected that characterization and earlier on Thursday, FBI Director James Comey told a congressional panel that court approval of the FBI’s request was “unlikely to be a trailblazer” in other cases.

While the case “will be instructive for other courts,” larger policy questions about reasonable law enforcement access to encrypted data will likely need to be resolved by Congress and others, Comey said.

Shares of Apple were barely changed and closed up less than 1 percent at $96.76.

Apple also raised the specter of courts ordering it to help in other cases in other ways, such as writing computer code that would turn on an iPhone microphone to help surveillance.

The company also criticized the Justice Department for publicizing the order, which would normally have been filed under seal.

“This is the only case in counsel’s memory in which an FBI Director has blogged in real-time about pending litigation, suggesting that the government does not believe the data on the phone will yield critical evidence about other suspects,” the company said.

Apple CEO Tim Cook said in an interview on Wednesday with ABC News that the company was prepared to take the case to the Supreme Court if necessary.

(Reporting by Dan Levine, Joseph Menn and Julia Love in San Francisco and Dustin Volz in Washington; Editing by Jonathan Weber, Bill Rigby and Richard Chang)