Australian Communications Minister Malcolm Turnbull has barely even finished introducing piracy site-blocking legislation into the parliament, and already the Helen Lovejoys of the world are trying to get it expanded into a much larger internet censorship scheme.

The legislation introduced into parliament in March would allow film studios, TV companies, and other copyright holders to apply to the court to get specific sites hosted outside of Australia and alleged to be primarily for the purpose of copyright infringement blocked by Australian internet service providers (ISPs).

The court will ideally examine the sites involved, and ensure that they meet all the conditions before ordering a block, though this is not guaranteed at this point.

If the ISPs are ordered to block a site, they can do so in a number of ways -- through DNS, IP address blocking, or URL blocking. The exact method, too, has yet to be determined.

Turnbull has stressed that because the court must approve sites being blocked, it is not an internet filter.

"It will be a court, not the government, that will determine which sites are blocked. Moreover, this is not an automatic process, but determined by a court with all of the normal protections of legal due process. In other words, a judge will make the decision, after hearing evidence and argument, not an algorithm in the software operating a router," he said.

The lack of an automated process of filtering types of sites means it is not a filter, according to the minister.

Others seem to disagree, however.

Far be it for me to allow the Australian Christian Lobby (ACL) to define the meaning of anything ever, but it has described the scheme as an "internet piracy filter" and called on the government to look at implementing a "default clean feed to protect children".

"It is only blind ideology that prevents Australia from implementing ISP filtering with a default clean feed to protect children from pornography," the ACL's Wendy Francis said on Tuesday.

"If technology can be used to protect content rights' holders revenue, surely it can be used to protect children."

This is a fundamental misreading of how the legislation operates, and also how the ISPs will implement it, because, as Turnbull has noted, it is not an automated filter of specific content, but rather just a block of specific sites.

How would the court determine whether a site that may host adult content should be blocked if it isn't primarily for adult content? Like, say, Tumblr?

If that is the approach the ACL wishes to take, though, I look forward to seeing it compiling a list of all adult sites it would like to see blocked. It will need to be quite exhaustive to be a "clean feed".

Regardless, the legislation now opens a door. If passed, it is only a matter of time before the Wendy Francises of the world and other groups want other websites blocked. It may not be this government that does it, but the temptation for future governments to appease conservative lobby groups with a quick change to the law in the future might be hard to resist.

The Coalition infamously backflipped on a policy for opt-out internet filtering in a matter of hours after ZDNet first revealed it two days before the federal election in 2013. The parliamentary secretary responsible for the short-lived policy, Paul Fletcher, declined to comment on the site-blocking legislation when asked about it on Tuesday.

Labor, the party behind the first, ultimately abandoned, "clean feed" policy, remains uncommitted to the site-blocking legislation. Labor's vote will be crucial in order for the Bill to be passed through the Senate, and reports have said that the party is prepared to back it.

Shadow Communications Minister Jason Clare would not reveal how Labor intends to vote, instead stating that through the parliamentary committee, he and Shadow Attorney-General Mark Dreyfus would examine the submissions and legislation.

Clare indicated that any site-blocking legislation may also need to have copyright reform addressing the disparity in IT pricing in Australia, and overhauling the Copyright Act to include a fair use prevision.

The government may also wish to consider a restriction preventing the expansion of the scheme to avoid another "clean feed" policy by stealth.