The Sophie Lancaster Foundation is campaigning for hate crime legislation to be expanded to include "alternative subcultures or lifestyle and dress" across Britain.
GMP said the change would enable officers to give more support to victims but would not necessarily lead to tougher sentences.
"People who wish to express their alternative subculture identity freely should not have to tolerate hate crime," said Assistant Chief Constable Garry Shewan.
The move was well received in London's Camden area, a youth hub where myriad subcultures mingle.
"Some people discriminate against somebody else because they are wearing a Slayer T-shirt or have long hair," said Jay White, 23, referring to the thrash metal band. "They deserve to be brought to justice."
White, a leather-clad, self-described "metalhead" said members of subcultures faced discrimination just like religious minorities.
"For a lot of people, metal is their religion," he said.
- Independent, AP