If it passes, the anti-piracy bill Stop Online Piracy Act, known as SOPA, would give entertainment industry companies unprecedented power to shut down the websites they think have infringing content, entirely and quietly.

The US congress held a hearing on Wednesday on the bill which was introduced by the House of Representatives last month.

RT has more details.

Correspondent: "Someone who has the ownership to give a piece of content and feels it's infringing, could then direct it to the department of justice and do that in a way that's not necessarily public, and then make complaints against it. It'll then give the department of justice certain powers to take that website off line. "

Lifehacker says SOPA will not stop downloaders of pirated content since they can still access a closed website by entering numeric IP address. What it will stop is the freedom of speech.

“Lots of trailblazing websites could look life piracy havens for the wrong judge. Tumblr, Soundcloud and either You Tube wherever people express themselves, make arts, broadcast news or organize protests, if there's any TV footage, movie clips or copyrighted music, may sting"

To block a website, the US government will use a domain name filtering techniques similar to that adopted by China and Iran.

EFF, Public Knowledge and some other organizations have named November 16th as American Censorship Day to fight for Internet freedom.

If the bill passes, it might hold Tech Giants like Google and Facebook responsible for piracy when they distribute certain content through search results or social exchange.

The Tech companies spoke out their concern in a joint letter to the Congress.

"... The bills as written would seriously undermine the effective mechanism Congress enacted in the Digital Millenium Copyright Act to provide a safe harbour for Internet companies that act in good faith to to remove infringing content from their sites...”

The Senate passed a twin bill  for SOPA earlier this year.

And Time says with bi-cameral, bi-partisan support, the chances SOPA will pass are excellent.

According to the Chamber of Commerce, the US companies lose 135 billion dollars a year to counterfeit piracy, which could explain why both parties support the legislation.

Still, Fox News reports lawmakers will consider changes to the bill to address concerns.