The number of Australians using virtual private network services (VPNs) has reportedly jumped in recent years, but consumer advocates are warning a new copyright bill could eliminate the option for Aussies hoping to keep their online activities under wraps.

A VPN helps Internet users anonymise what they do on the Internet. Going online via a VPN service provides a secure, encrypted tunnel through which data can be passed between a user and a website or other online service. This essentially masks the location and identity of the original user.

The service is often used to circumvent geoblocks on foreign film and television — it's how all those Aussies were watching American Netflix before the streaming company launched locally — but also for more legitimate aims, like maintaining privacy online, where hacking and scams are all too common.

Under the Australian government's proposed site-blocking law — the Copyright Amendment (Online Infringement) Bill 2015 — Australians could find their access to VPNs blocked if the service's "primary purpose" is found by a federal court judge to be facilitating copyright infringement.

The Electronic Frontier Foundation (EFF), the Australian Competition and Consumer Commission (ACCC), and consumer advocacy group, Choice, among others, have raised concerns about the bill's vagueness as to what it covers. The legislation uses the undefined term "online location" — which could be a VPN, website or cloud storage — and so they're worried this broad term could see could see many VPN services blocked in Australia.

The EFF said in their submission to the government, the bill seemed to cover not only websites that host copyright infringing content, but also sites that "facilitate the infringement of copyright" or have the "primary purpose" of infringing copyright.

"This could be read to ensnare the operators of Virtual Private Network (VPN) services, some of whom (such as getflix.com.au) specifically market their services for their ability to access blocked or geoblocked content," the EFF wrote. "Nonetheless VPN services themselves are typically general-purpose Internet services that can be used for many other lawful purposes, and it seems disproportionate to allow these lawful services to be blocked merely on account of the way that they are marketed."

Australia's Attorney-General, George Brandis, is in charge of the site-blocking bill. Image: Corbis Images

At a public hearing into the bill in Sydney on Friday, Fiona Phillips, executive director of the Copyright Council, attempted to address these concerns. She said that while some VPNs are used to circumvent geoblocks so users can access content on U.S. sites like Hulu or HBONow, circumventing geoblocks was not a copyright issue.

"That is not the object of this legislation, we can all agree ... However, if I were to set up a VPN called ‘Highway To Pirate Bay’," she said. "That service could and should be the subject of the legislation in the same way the UK decision on Popcorn Time this week held up an app as facilitating infringement."

At the hearing, a spokesperson from the Attorney-General's Department — the executive body responsible for the legislation — also recognised VPNs can be used for legitimate purposes. "The bill doesn't target VPNs, but it doesn't exclude VPNs," he said. "The bill doesn't target a particular technology ... it's technology neutral."

Further clouding the issue, the Communications Minister, Malcolm Turnbull, has said Australia's Copyright Act does not make it illegal to use a VPN to access overseas content.

The parliamentary committee scrutinising the bill is due to report back any recommendations to alter it by May 13. It remains to be seen whether VPNs are effectively finished with Down Under, or whether Australians can keep browsing privately.