Photo: Aereo founder and CEO Chet Kanojia

Aereo is now at odds with a federal government agency as part of its ongong legal battle with the television industry.

The Justice Department filed a brief with the Supreme Court on Monday in support of a group of broadcast networks suing online TV streaming startup Aereo, Re/code reports.

Lawyers for the Justice Department argue in the brief that Aereo's service, which allows users to access TV content on the Internet through personal antennas, infringes on broadcasters' copyrights and asked the court to reverse an earlier decision by federal courts in New York and Boston that ruled in favor of the startup.

The Justice Department said Aereo's service allows consumers to "gain access to copyrighted content in the first instance--the same service that cable companies have traditionally provided," Re/code reports. But unlike cable companies, Aereo doesn't pay licensing fees to broadcasters.

Major broadcasters, including ABC, CBS, FOX, and NBC, sued Aereo shortly after its February 2012 launch. The suit claims the company offers an illegal service due to the fact that Aereo doesn't pay to pick up the signals it streams to users.

The federal courts in New York and Boston ruled in favor of Aereo's argument that it is legally transmitting protected "private performances" to individual customers. 

In an interview with Time on Sunday, Aereo founder and CEO Chet Kanojia said he is confident in his company's case as the startup prepares to defend itself in a Supreme Court against the nation's top four TV broadcasters. Oral arguments in the case are set for April 22.

Aereo's service is currently available in 10 metro areas, and the company has plans to expand to more than a dozen other areas.