Google was responding to Viacom's copyright infringement lawsuit against YouTube file-sharing, in a US federal court filing last month.
Google said: "By seeking to make carriers and hosting providers liable for internet communications, Viacom's complaint threatens the way hundreds of millions of people legitimately exchange information, news, entertainment and political and artistic expression."
Viacom, which owns MTV, VH1, Nickelodeon and Comedy Central, sued Google in March in the US District Court in New York for copyright infringement "on a massive scale" after requesting that more than 100,000 videos be removed from YouTube.
Google is demanding a jury trial in response to the allegations, according to legal papers filed yesterday.
Google's defence against allegations of failing to prevent YouTube users from pirating Viacom clips rests on 1998 copyright protection law. The Digital Millennium Copyright Act (DMCA) protects internet service providers that act quickly to block access to pirated online materials, once a copyright holder claims infringement.