In a submission to the parliamentary inquiry into the Copyright Amendment (Online Infringement) Bill 2015, the Communications Alliance, which represents telecommunications providers in Australia, said the cheapest methods of blocking piracy websites under the scheme were likely to incur more "collateral damage" in inadvertently scooping up legitimate websites.

It cited the Australian Securities and Investments Commission's bungled blocking of fraudulent websites via their internet protocol (IP) addresses in 2013, which meant thousands of legitimate websites were taken out in the process.

The alliance noted the most accurate of three website-blocking methods – targeting a URL (web address) – was also the most expensive but argued internet service providers (ISPs) should be able to choose which method they employed in order to keep their costs down.

Further, it asked that the government explicitly grant ISPs "an indemnity, immunity, or safe harbour" if businesses or individuals sought legal action for their websites inadvertently being taken offline under the scheme.

The other methods the alliance cited were blocking access at the level of the domain name, i.e. google.com.

The amendments to the Copyright Act are before the House of Representatives and give scope for copyright owners to apply for an injunction in the Federal Court, forcing Australian ISPs to block overseas websites whose "primary purpose" is to infringe, or "facilitate an infringement of", copyright.

However, the Australian Digital Alliance, which represents both public and private interests in the copyright debate, warned of the potential for "scope creep" under the legislation, which could mean legitimate websites were lumped in with ones that had a more obvious purpose of infringing copyright.

ADA executive officer Trish Hepworth said website blocking was a "blunt instrument" and called for ambiguous terms in the legislation to be tightened.

"[Scope creep] means that [internet] subscribers may be unable to access legitimate content or legitimate tools; a potential impingement on their freedom of expression and freedom of access to information and culture, which has not been adequately recognised," Ms Hepworth said.

Various legitimate services had been taken offline under website-blocking regimes overseas, including in India and Britain, where a trademark violation had "no recourse to parliament".

Other services potentially in the firing line included URL shorteners, file-sharing services, cloud storage providers, Google Docs, VPNs, torrenting services, chat services, browser plug-ins, conversion tools, and blogs or Reddit threads discussing techniques or sites that may be used to infringe, Ms Hepworth said.

Consumer group Choice called the scheme an "internet filter".

It said the Communications Alliance was right to raise the point of "collateral damage".

"Any blocking exercise risks collateral damage," Choice campaigns manager Erin Turner said.

"This bill is guaranteed to present problems, it won't present solutions . . . it will only frustrate Australians."

However, in a colourful rebuke, Village Roadshow co-chief executive Graham Burke, making a submission to the inquiry on behalf of Australian rights holders, argued blocking access to copyright-infringing material was effective.

Mr Burke cited evidence that blocking The Pirate Bay in Britain had reduced piracy more than 80 per cent, though the figure did not account for internet users in Britain potentially accessing the site from overseas using virtual private networks.

Mr Burke said Village Roadshow strongly supported the website-blocking legislation.

He said Australia's film and television drama production industry would be "shut down" without it.

"Like a factory spilling effluent into a river, the unintended consequence of their [ISPs] business is piracy, with its damning effects on our people, our culture and the economy," Mr Burke said.

He said Australians should ignore ISPs' "scare tactics" that implementing anti-piracy measures would result in higher costs for consumers.

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