The band should have plenty of fans here, hailing as they do from "Hong Kong West", aka Vancouver. Prime movers in the west coast Canadian punk scene of the early '80s, the band's popularity as one of the great, sometimes under-acknowledged, key figures of punk, and also of indie-rock and thrash metal, extends around the world.

They're so popular at home that Vancouver even has a D.O.A. Day - December 21. It was introduced by former mayor Larry Campbell in 2003 to celebrate the band's 25th anniversary, not just because he's a fan, but also because of the band's commitment to supporting causes such as anti-racism and environmental awareness.

While D.O.A. have never visited Hong Kong, they did play four shows on the mainland five years ago - two in Beijing, and one each in Shanghai and Wuhan - all alongside young local punk bands. Keithley says the shows took him by surprise. "The audience was really young. It was like going back to England in '81-'82 - everyone had mohawks and studded jackets."

Playing to such a fresh-faced audience, he adds, was also a refreshing experience for a band with such a loyal fan base. "It was really interesting - there'd only be a few people who knew a few D.O.A. songs. In Shanghai, there were lots of expats and lots of recognition. For the other shows, it was like going out on tour for the first time - you've really got to impress the crowd and win them over."

As a member of D.O.A., Keithley, who was born Keighley but changed it because no one could pronounce it, is known by the charmingly typical punk sobriquet of Joey Shithead, something that the 57-year-old rocker says people in his hometown still sometimes shout at him in the street.

Inspired by punk's famous DIY ethic, since the start, he has also run his own label, Sudden Death Records. It was initially a part-time job, but it has become a fully fledged label that has released 90 records since 1998; 20 that sell and 70 that don't, says Keithley. "I started the label just to put out D.O.A. records, and then friends starting asking me to put out their records, too. I knew a bit about the record business, but not as much as I thought."

He's certainly worked with some punk royalty, including Jello Biafra from US punk outfit Dead Kennedys and British acts Sham 69 and The Vibrators. A particular highlight, he says, was putting out music by British punk legends The Damned, "who were the first punk band I ever saw on TV".

He even helped Canadian pop-punk band Pointed Sticks to reform and start touring again after a 15-year gap, when he saw they were still popular in Japan.

Like the entire music industry, Sudden Death has been affected by the dramatic growth in digital music. "It's been really tough - about half of my friends running small labels have gone out of business. It started about eight years ago and it peaked about two to three years ago, when digital downloads accounted for 50 per cent of all music sales," he says.

Since then, however, he says there's been a steady increase in vinyl sales.

As well as musician and label boss, Keithley's long-held political beliefs have recently led him to seek yet another role: politician. D.O.A.'s lyrics have always been filled with fiery political protest, and they've worked tirelessly for good causes. "We were pretty much known as the city's benefit band: 'If you've got a cause, call them.'"

Keithley says that when he realised his job had made him particularly good at articulating ideas, going into politics was a logical next move. "I've probably done a thousand interviews, a lot of them live, and I've developed a sense of how to say things, what to emphasise and what not to emphasise." He has stood for nomination twice for the small Green Party of British Columbia, and recently for the mainstream, left-leaning New Democratic Party, but missed out. He says he's going to keep trying.

He sounds resigned when he says he thinks he's probably too radical and too plainly spoken for most political parties, even ones with a progressive agenda. In the recent campaign, "when it looked like I'd win, the party threw its resources behind my opponent, and I lost by five votes. They didn't want an independent candidate. The guy they backed ended up losing miserably."

An old-fashioned campaigner who prefers meeting people in the flesh, Keithley estimates he knocked on about 3,000 doors during the campaign; about 25 per cent of the people opening the doors recognised him. "A lot of them were shocked that I was wearing a suit, which surprised me. They thought I'd wear a jean vest and a mohawk?"

His music, meanwhile, remains as resolutely political as ever, although he fears he might be part of a dying breed. "Punk rock now is way more popular than it was when I was young, and while it might be loud and fast, there's not a lot of content in the lyrics. Rap was the last great kick-your-ass music," he says.

"Then you got grunge, and with it the start of people being apathetic. When I was young, we'd organise gigs against racism, against nuclear power - that was what we did. And I'm sure someone eventually is going to take that and run with it," he adds.

Before his next shot at political office, D.O.A.'s never-ending farewell tour rolls on. After Hong Kong, there are some dates in Florida, and then a summer festival tour of Europe. Keithley says the band are even planning to work on some new songs - so it doesn't sound like the end of that final tour is imminent. "Since I started retiring," he says, "I've never had so many offers in my life."