How a common law enforcement tool could be abused to spy on you illegally

Privacy advocates are warning that the legal gray area in a key court case may make it easier for the government to spy on Americans illegally.

By using what's called a pen trap order -- a type of judicially approved surveillance mechanism that's only supposed to capture metadata about electronic communications -- it appears that the government has the theoretical ability to capture the content of those communications as well. The case involves Lavabit, the secure e-mail service used by National Security Agency leaker Edward Snowden.

Broadly, the case is about whether the government can force an Internet company like Lavabit to hand over its encryption keys. In a ruling, a federal appeals court sided with law enforcement. But a closer look at just how the government can obtain the keys has civil liberties scholars very worried. If the government can use an order that's restricted to metadata to obtain keys it could then use to decrypt content, then a nefarious actor could gain access to content without jumping through the judicial hoops necessary for demanding content.