MARK OF THE MOB: Dennis Makalio sits the grave of a Mongrel Mob member at Whenua Tapu cemetery. He plans to challenge a proposed ban on offensive insignia on headstones

The Mongrel Mob is pledging to fight Porirua City Council all the way to the Supreme Court if it goes ahead with a ban on offensive insignia on headstones.

The gang says it is being targeted by the council, most notably at the Whenua Tapu cemetery between Plimmerton and Pukerua Bay, which already has some Mongrel Mob headstones.

The proposed changes were sparked by an incident in 2008 when a widow moved her husband's body at Whenua Tapu after taking offence at gang insignia on a neighbouring headstone.

The council can dictate only the size and installation of headstones, not content, but under the proposal – sparked by complaints about gang insignia and mottos – "no individual monument shall cause offence".

About 10 years ago the Mob replaced the words "Sieg f...ing heil" – a Nazi salute appropriated by the gang – with "SFH" on some new headstones.

However, Whenua Tapu has no "SFH" tombstones, and just four with the Mongrel Mob insignia.

Council asset management and operations general manager Peter Bailey said the plan – which did not necessarily ban all gang insignia – was merely documenting existing practice.

If approved in a full council meeting tonight, the bylaw change will go out for public consultation as part of the Porirua Cemeteries Management Plan.

Mongrel Mob member Dennis Makalio said the move was a form of racism and a targeted attack by "certain councillors", whom he would not name.

The gang was happy to remove swear words, but taking down anything else that had previously been approved would be unlawful, disrespectful and culturally insensitive, he said.

He had sought legal advice, and planned to take the case to the Human Rights Commission and, if necessary, to the Supreme Court.

Mob membership was similar to religion and some members, including himself, wished to have the gang's insignia on their headstones, he said.

Porirua City councillor Litea Ah Hoi said Mr Makalio had to "grow up". She did not regard the change as "gang bashing".

"You can't play the race culture card whenever it suits," she said.

"We are talking about a policy in regard to offensive words and graphics."

Porirua Mayor Nick Leggett stressed the change was not specifically gang related and was aimed at all offensive headstones.

"It's about guidelines that protect, I suppose, common standards of good taste."

If the bylaw was changed, the legal risk would be factored in and the council would be willing to defend it in court.

Lawyer Steven Rollo, who was instrumental in sending Whanganui's anti-gang patch bylaw back to the drawing board, said courts would consider whether or not council powers were being exercised appropriately.

Wellington City Council's Richard MacLean said the council screened headstones. "If a reasonable person found the headstone offensive or objectionable, we would turn it down."

Hutt City Council and Whanganui District Council said they had no specific legislation about the matter.

Human Rights Commission spokesman Gilbert Wong said the Mob could complain to the commission, which would decide whether it had the authority to investigate.