Secure email provider Lavabit just filed the opening brief in its appeal of a court order demanding it turn over the private SSL keys that protected all web traffic to the site.

The government proposed to examine and copy Lavabit’s most sensitive, closely guarded records–its private keys–despite the fact that those keys were not contraband, were not the fruits of any crime, were not used to commit any crime, and were not evidence of any crime. Rather, the government obtained a warrant to search and seize Lavabit’s property simply because it believed that the information would be helpful to know as it conducted its investigation of someone else.

As first reported by WIRED last week, the formerly secret July 16 order under appeal came after Texas-based Lavabit hesitated to circumvent its own security systems to comply with earlier orders intended to monitor a particular Lavabit user’s metadata, defined as “information about each communication sent or received by the account, including the date and time of the communication, the method of communication, and the source and destination of the communication.”

The name of the target is redacted from the brief, and from unsealed records in the case. But the offenses under investigation are listed as violations of the Espionage Act and theft of government property — the exact charges, in the same court, that have been filed against Lavabit’s most famous user, NSA whistleblower Edward Snowden.

The appeal brief correctly notes that the SSL keys would have allowed the government to eavesdrop on any or all of Lavabit’s 400,000 users as they used the site, though the government promised it wouldn’t do that.

After losing a court argument challenging the order in August, Lavabit founder Ladar Levison turned over the key and shut down his business, mooting any attempt at surveillance.

He appealed to the 4th U.S. Circuit Court of Appeals. The government’s reply brief is due

November 4. Levison has raised approximately $90,000 in an online fundraising drive to finance his appeal.