A Perth judge has described a former member of online activism group Anonymous who helped hack into websites as an "immature creep" and a "pest" who had never grown up.

Adam John Bennett, 42, was today given a suspended sentence for six charges including aiding another person to cause the unauthorised impairment of electronic communications.

Five of the offences occurred in November 2012, when members of the group Anonymous hacked into websites around the world.

Bennett, a long-time lifesaver at Scarborough Beach, used the pseudonym 'Lorax' for his online activities, and had an online radio show, as well as thousands of followers.

The court was told when Bennett's Scarborough home was searched in 2014, a Guy Fawkes mask was found, along with audio streaming and studio equipment.

It was alleged there were plans for a "mass defacement" of sites planned to mark Guy Fawkes' Day in 2012.

The court was told Bennett helped a juvenile in NSW dubbed 'Juzzy' to hack into a variety of sites, including those operated by the Australian Agency for Education and Training, the Australian Film Institute, Anchor Foods, and the Food Industries Association of Queensland.

When the public tried to access a hacked site, they found a message from the group in red text on a black background.

Prosecutor Patricia Aloi told the court "the plan was to get a much larger number of sites".

She said the "impact could be described as a nuisance, could be described as lost productivity", and such offending could escalate.

Ms Aloi said the Commonwealth believed a custodial sentence was appropriate.

Lawyer argues rant was one of 'political ideology'

Acting on behalf of Bennett, Darren Renton told the court the hacked web pages were accessible, and only the front page had the Anonymous "rant".

He agreed with Justice Phillip McCann's description of the offences as being "like barricading the front door and not the side door".

Mr Renton said the Anonymous rant was one of "political ideology" and there was no suggestion of financial or monetary gain, or sensitive information being accessed.

While the result was something akin to "digital graffiti", he said his client accepted he was breaking the law, and it was an illegal way to put forward a political view.

A sixth offence involved the website of Bennett's employer Cancer Support WA and that of HotCopper.

Bennett tested the sites for vulnerability to the Heartbleed security bug, and tried to access confidential information.

Mr Renton spoke of other communications Bennett had with various companies, and the Supreme Court of Tasmania, and Senator Nick Xenophon, in which he highlighted how they were vulnerable to hacking.

Bennett used the Anonymous Australia Twitter account, and Mr Renton said his client was being "altruistic".

But Justice McCann said the actions were more like bullying and intimidation, including when Velocity Internet was told "you have been warned".

Rants 'a recipe for anarchy'

Justice McCann was highly critical of Bennett, who he referred to as a "creepy pest" and an "immature creep who doesn't mind his own business".

He said "as a private citizen he has no business pestering people like Nick Xenophon".

Justice McCann said there was a "high level conspiracy to commit anarchist acts".

He highlighted part of the rant which said information about corporation and governments should be publicly available, and called it "a recipe for anarchy".

Justice McCann said it was not a political ideology, more like "immature rants of the schoolyard".

He said Bennett, who was in his late thirties when the offences occurred, was "grossly immature" with an "unjustified sense of self worth".

But he said to jail Bennett, who had "basically never grown up", would make him a martyr, and he should instead be given the "21st century equivalent" of being in the stocks.

Justice McCann said while there was "insufficient evidence of damage" by the hacking in 2012, there was malice.

He said the use of the internet was a privilege and not a right.

Bennett was given a sentence of two years' imprisonment, suspended for two years, as well as 200 hours of community service and an intensive supervision order.

Bennett first entered guilty pleas in October 2015, and the fact he had shown remorse was taken into account.