In a wide-ranging show of solidarity, dozens of Apple's tech industry competitors and contemporaries filed amicus briefs today in support of the company’s stand against the FBI. In one instance, heavyweights including Google, Microsoft, and Facebook set aside their corporate rivalries to file jointly. Twitter, Airbnb, Ebay, Reddit, and a half dozen other Internet luminaries joined forces to file another brief.

The briefs, which argue that Apple should not be compelled to create software to help the FBI break into an iPhone that had been in possession of San Bernardino shooter Syed Farook, are meant to bolster the Cupertino company’s legal case. Intel and AT&T—yes, the same AT&T that had a secret spying pact with the NSA—filed their briefs solo. The ACLU, Access Now, and the Wickr Foundation, and a group of security experts have lent their support as well, with more companies, experts, and institutions expected to join in by the end of the Thursday deadline set by the case's judge Sheri Pym.

While this seems like a natural cause for the technology industry to rally behind, many tech leaders were initially slow to express support for Apple in the matter. As the New York Times reports, several companies also hesitated to support Apple publicly. Some expressed concern over whether this was the right fight to pick, while others worried about public perception.

Those concerns appear to have been allayed, at least on the part of the companies who filed Thursday. Their briefs in support of Apple are unequivocal, and use language as forceful as the company’s own.

Apple's all-star Internet friends went aggressively after the government's interpretation of the All Writs Act of 1789, which it's using to justify its order to compel Apple to help hack the iPhone:

The All Writs Act does not authorize the government to make an end-run around this important public debate and our nation’s legislative processes... This extraordinary and unprecedented effort to compel a private company to become the government’s investigative arm not only has no legal basis under the All Writs Act or any other law, but threatens the core principles of privacy, security, and transparency that underlie the fabric of the Internet.

While pointing out that applying the AWA here would give law enforcement boundless authority:

The government’s demand, at its core, is unbound by any legal limits. It would set a dangerous precedent, creating a world in which the government could simply force companies to create, design, and redesign their systems to allow law enforcement access to data, instead of requiring the government to use the measures, and meet the requirements, of legislatively enacted statutory schemes.

And could have equally limitless repercussions:

The government seeks unbounded authority to compel Apple to design software that does not currently exist and that will circumvent and undermine security measures intended to protect its users’ data. This principle could require companies not just to turn over one user’s information but to weaken security measures created to protect all users. Granting the government such extraordinary authority, without any set rules or legal protections, will not only erode user privacy and security and defeat users’ interest in transparency, it will undermine an existing legislative framework balancing competing interests and policy considerations.

Google, Microsoft, Facebook, Amazon, Yahoo et al

The most impactful brief came from Google, Microsoft, Facebook, Yahoo, and Amazon, who were joined by 10 other prominent technology companies.

They made clear just how outdated the All Writs Act of 1789 is:

That was fifty years before the telegraph originated and almost a century before Alexander Graham Bell made the first telephone call... Now, 200 years later, the government endeavors to reinterpret the All Writs Act as an open-ended source of new powers.

And that the 1977 United States v. New York Telephone case the FBI has cited as precedent for the government to compel companies to give technical assistance isn't much better:

It is dangerous to extend that limited endorsement of judicial power over third parties [granted by US v. NY Telephone] to situations the Supreme Court never could have envisioned—and all the more troubling where the Court itself declined to opine on "the diverse contexts in which [third party duties] may arise... This court should therefore exercise caution in how it applies a decision from an era in which concepts like "cell phones" and "the Internet" where unheard of.

If anything, they point out, precedent as recent as 2014 says that the law should evolve along with technology:

In Riley v California, the Supreme Court explained that cell phones had alterd the reasonableness of a full search incident to arrest. The Court observed that modern cell phones "are based on technology nearly inconceivable just a few decades ago," when the only relevant search-incident-to-arrest precedents had been decided.

Besides which, opening a cell phone in 2016 is nothing like opening someone's safe, or even searching their home, as the FBI has implied:

Americans live their lives on their phones now. They store their emails, their conversations, their appointments, their photos, sometimes even their medical information, all in a device they carry in their pockets. Cell phones are the way we organize and remember the things that are important to us; they are, in a very real way, an extension of our memories.

They also make the case that Congress, not the courts, should decide, as it has over the last few decades with laws like the Wiretap Act, FISA, and most recently CALEA, which regulates technological surveillance:

In light of rapidly evolving technology and its tremendous social benefits, Congress is better suited to confront the issues here. And indeed, Congress has already grappled with these issues on many occasions—leading to a comprehensive legislative scheme for regulating investigative methods.

And they put into perspective the burden companies—and their employees—would have to bear:

The government seeks the power to conscript technology companies' engineers to develop products that they do not want to create, and which they would not create absent government compulsion. That is a far cry from the "nonburdensome technical assistance" that the All Writs Act authorizes... With enough time and resources, amici's engineers could possibly come up any number of new versions of their companies' products that circumvent or undermine their pre-existing data-security features. But those new versions would not be the same product anymore. Box would not be Box; Gmail would not be Gmail; WhatsApp would not be WhatsApp; and so on.

While reminding the court that code is legally considered speech:

Writing computer code can be a creative, complex, and expressive task, and it is a form of protected speech under the First Amendment.

Apple and the FBI will return to court on March 22. Judge Pym has no shortage of reading material with which to keep herself occupied in the meantime.