Silicon Valley's tech giants may be staunch rivals in the marketplace but are displaying a rare united front in backing Apple's battle against the FBI. Google, Facebook, Twitter and even Microsoft are rallying behind the iPhone-maker against the San Bernardino order that Apple has challenged.

Apple filed a motion to vacate the order passed on 16 February to aid FBI in decrypting an iPhone 5C used by Syed Farook, who along with his wife Tashfeen Malik, shot and killed 14 people in San Bernardino in December 2015.

"This isn't a case about one isolated iPhone. No court has ever authorised what the government now seeks, no law supports such unlimited and sweeping use of the judicial process. In order to comply with these demands Apple would need to create a new 'GovtOS' that has the potential to be used on hundreds of phones now in law enforcements possession in conflict with existing law as well as the First and Fifth Amendment of the United States Constitution," says the court filing.

The order goes on to mention what Apple CEO Tim Cook has constantly harped upon — the bigger threat of privacy infringement. It says if the government can ask for the hacking of a single device it can ask for many others and in future lead to greater surveillance requests that will have no limits. The company even compared the order to a pharma firm being forced to produce lethal injection drugs or a journalist who plants a false story in order to help lure out a fugitive.

Meanwhile, fellow tech giant Microsoft publicly announced that it supports Apple and will file a friend of the court opinion next week backing its competitor in these desperate times. "We at Microsoft support Apple and will be filing an amicus brief next week," said Microsoft president Brad Smith at a congressional hearing. Former Microsoft boss Bill Gates, who in some media reports was earlier quoted as saying that Apple should help the FBI, has now clarified that he does not stand on one side and thinks there is a larger debate that needs to be addressed.

Many reports indicate that Google, Twitter and Facebook, whose CEOs have already lent support for Apple, will join with Microsoft. E commerce venture Amazon is expected to join in as well. Similar briefs are also expected to be filed by the American Civil Liberties Union, the Electronic Frontier Foundation and Amnesty International.

The other side

Meanwhile, the FBI is not bucking down either as FBI director James Comey told a House panel that he did not "fully understand'' Apple's opposition in the San Bernardino case. "This is a single phone in a very important investigation. I'm a big fan of privacy; I love encryption too, but if we get to a place in American life where certain things are immune from a judge's order, then we are in a very different world,'' said Comey after Apple filed its motion.

The tiff between the iPhone maker and the security agency has heightened to such an extent that Apple's top lawyer is expected to testify before a congressional panel next week. The hearing, scheduled for 1 March, will have the Congress for the first time question an Apple representative as to why the company rejected the court order. The judiciary committee hearing is likely to be the first of several congressional oversight opportunities.

As far as legislation on the subject is concerned, in 2015, the Obama administration ruled out seeking legislation to force mobile or software companies like Apple to design "backdoor" access to government investigators. However, two lawmakers Michael McCaul from the Republican party and Senator Mark Warner from the Democrat side say they will introduce a bill in Congress next week seeking to form a commission tasked with addressing issues on digital security that have put authorities and private companies at odds. Earlier reports have also suggested that fresh legislation may be on the cards to bring companies like Apple under a necessary surveillance ambit.