Privacy advocates, civil liberties groups and law councils have outlined their “great concern” about the government’s proposed counter-terrorism legislation, including that a revised definition of what a computer is could allow anything connected to the internet to be targeted in mass surveillance.

There was also strong criticism of proposed broad powers which threaten to criminalise journalists receiving and publishing leaked intelligence documents.

The joint parliamentary committee on intelligence and security (JPCIS) continued on Monday to hear submissions to its inquiry on the changes proposed by the attorney general, George Brandis. It questioned several lawyers’ associations, the civil liberties councils, the Electronic Frontiers Australia (EFA) and the Media, Entertainment and Arts Alliance (MEAA).

Among the concerns raised about the tranche of changes to counter-terrorism legislation – which would allow Asio agents to use force in operations, allow more co-operation between intelligence agencies on operations, and increase penalties against people disclosing intelligence information – was that a revised definition of “computer” could allow intelligence agencies access to almost any computer.

Representatives of Gilbert and Tobin focused on the deviation of the definition of a computer from that which was recommended by the committee in 2013, which added the words “and includes multiple computers operating in a network”.

The proposed changes define a computer as all or part of one or more computers, computer systems, computer networks, or any combination of the above, and do not define what a “network” is.

This raised the question of whether all computers that connect to the internet could potentially be accessed by intelligence agencies

for the purposes of surveillance of one target.

Senator Penny Wong asked Gilbert and Tobin’s Keiran Hardy whether the potential for the term “computer” to apply to all computers connected to the internet was something the centre thought was “really plausible” under the proposed definition. Hardy replied: “That’s probably the broadest definition you can think of.”

“Our concern is more that a network could extend to any computer located on a university campus … or work premises,” he said, adding the concern that a network was not defined by location under the proposed changes.

“There is nothing in the legislation so far to even explain what the potential limitations to that is,” he said.

Deputy chair of the committee, Labor MP Anthony Byrne, suggested that legislation could include a requirement to establish a link between a person targeted by intelligence agencies and computers targeted.

“That is the sort of context we feel needs to be in the legislation,” said the centre’s founding director, Prof George Williams, who added that such a link would be a move towards “a more tailored approach rather than networks at large”.

The JPCIS earlier heard from Jon Lawrence, executive officer of the EFA, who also voiced concerns about the definition. He said the arguable ability to apply it to “the entire internet” posed not just privacy risks to non-suspect people, but also posed “significant potential issues with this power in terms of the credibility of evidence in any court case”.

Proposed amendments to Asio powers seek to include the right to target any computer on the premises specified in a search warrant or any associated with, used, or likely to be used by a person specified in the warrant.

The Law Council of Australia submitted that the definition of premises was “very broad” and “could include, for example, a head office in which thousands of people are employed”.

There was reserved agreement among most attendees that the retaining of the national security legislation monitor was a positive step, and that the inspector general of intelligence and securities (Igis) does and could continue to provide oversight.

The committee also heard several submissions concerning a proposed amendment which could potentially criminalise the actions of a journalist who receives and sits on leaked intelligence information.

“The challenge for modern democracies is not to extend the criminalisation chain, but to ask what should be criminal, what should be civil, and what should be applauded,” the federal secretary of the Media, Entertainment and Arts Alliance, Chris Warren, said.

“The problem with this legislation is that the distinction is never made.”

The Law Council of Australia had earlier told the committee the legislation made it particularly risky for journalists to publish intelligence leaks because of secrecy provisions around security intelligence operations (SIOs).

“It limits freedom of speech for the media, because for any information about intelligence operations they won’t report it out of fear that it relates to a SIO,” said the council’s policy lawyer, Natasha Molt.

Liberal senator David Fawcett suggested if that was the case then they should not anyway.

“If the concern is to inappropriate conduct … as long as there is an avenue to report to an independent authority, why do they need to publish?” he asked.

“It’s almost like you’ve redefined the function of the press in Australia,” said barrister Stephen Keim SC.

The submission by the MEAA said the data surveillance revealed by NSA whistleblower Edward Snowden had created a new environment which “requires journalists to be mindful of how they interact with confidential sources.”

The committee asked Warren why “being mindful” was sufficient, rather than “criminalising the most egregious breaches of the information” given the risks identified in anti-terror operations in Australia, and an “increased threat environment”.

Warren said the criminalisation went a lot further than egregious breaches.

“It criminalises not only the action of releasing information, it criminalises the receipt of that information by journalists, it criminalises the work of journalists themselves,” he said.

“The way it’s currently drafted, if the journalist receives and holds the information, they’re committing an offence with quite substantial penalties in a way that comparable jurisdictions’ law don’t provide.”

In response to a question from Liberal MP Andrew Nikolic, Warren said decades of experience gave journalists the skill to assess the risks associated with leaked information, and said there were multiple cases when journalists “sat on” information related to intelligence agencies or high level crime until it was “safe” to disclose.

“There’s not a record of journalists who have been – to use an offensive term used here last Friday – reckless,” he said.

Coalition MP and former attorney general Philip Ruddock replied: “You defend them all. I’d have to say I think there are quite different practices despite who you’re speaking about.”

Ruddock had earlier on Monday said “the recklessness test is really about … are [journalists] going to make adequate inquiries to satisfy themselves that this is some evil that needs to be addressed.”

Greg Barnes, representing the Australian Lawyers Alliance, also presented his submission to the committee but faced no questions. He said Ruddock’s comments demonstrate a thought process “which has led to a far too cosy alliance between some journalists and security agencies.”

Barnes told Guardian Australia the WikiLeaks and Snowden revelations had led to “community discomfort about secrecy on the part of organisations like Asio” and about the idea that media bringing such revelations to light could be criminal.

“The bill is a step in the wrong direction in that regard,” he said.

“I was struck by the fact that no one seemed to disagree with that proposition.”

Last week the PJCIS heard from the IGIS, Vivienne Thom who called for clarification from the government on the legislation and the powers it would bestow on intelligence agencies.