Any burnt-out politicians in need of sympathy should steer clear of Joe de Bruyn — the leader of the country’s largest and most ideologically fervent union, the Shop Distributive and Allied Association.

The man Gough Whitlam famously described as a “Dutchman who hates dykes” says he works harder than most pollies — and wields more influence than them too.

“You have far more impact as a union leader than being a member of parliament — absolutely, particularly at a union like ours,” de Bruyn tells The Power Index in a rare extended interview.

As for politicians: “They just spend a lot of time hanging around doing nothing or sitting in the chamber listening to other people speaking. It’s that lack of activity that would be of no interest to me.”

You can’t blame de Bruyn, who’s led the 215,000-strong retail union since 1978, for a lack of false modesty. He’s outlasted five prime ministers and, at 62, maintains a schedule so punishing it makes most workaholics look like bludgers.

De Bruyn, a member of the ALP’s elite national executive, has a platoon of loyalists in parliament and controls the biggest bloc of votes on the ALP conference floor. He uses it to pursue a hardline anti-gay marriage, anti-abortion and anti-stem cell research agenda.

Although best known for his staunch conservatism, it’s in the industrial arena where de Bruyn has the most clout. He negotiates with the nation’s biggest employers — Coles, Woolworths, McDonald’s, Myer, Bunnings — on behalf of millions of employees.

“Joe is an incredibly organised, structured, well-considered union leader,” says former ACTU assistant secretary Chris Walton. “He’s often giving history lessons to the employers he deals with. He knows the industry back to front. In many countries, retail employees are part of the underclass but not in Australia — that’s because of the SDA.”

De Bruyn’s famously fastidious approach is on display when The Power Index meets him at 8.30am in the SDA’s national office, deep in the heart of Melbourne’s latte belt. He’s already cut out, highlighted and filed away an article from that morning’s Australian Financial Review headlined “Woolworths executive pledges profit growth”.

“We’re in negations with Woolworths [and] this is all going to be quoted back at him at our meeting next week,” he says with a grin.

“I’m just sitting back with the company and saying, ‘we won’t accept your offer; it’s not good enough.’ I’m just arguing with them intellectually and going higher and higher in the company. It will force them, ultimately, to improve their offer. I know that. And when they get high enough we’ll accept it.”

De Bruyn’s pragmatic approach infuriates his critics, who accuse him of disempowering his members and stitching up soft deals in exchange for access to the workplace. It’s a charge de Bruyn vehemently denies.

“By going about our job in a sensible way we’ve been able to exert a remarkable influence over companies,” he says — citing a 2008 deal that won paid maternity leave for Woolworths employees.

“We do not trade wages or conditions for access and we never have. The one thing we don’t do is go to employers and threaten their business. I think that by working behind the scenes and talking to the key decision makers in the company we’re more likely to get a change of heart and a higher wages offer than by going public and bagging the company.”

De Bruyn’s industrial tactics, while hotly debated, aren’t nearly as controversial as his staunch Catholic views — and willingness to use his factional muscle to enforce them.

During our interview, he retells the story of a US father who was supposedly jailed for seeking to withdraw his children from any classes where gay marriage was taught as legitimate: “This is what the future looks like when you go down this path.”

Legalising gay marriage, he argues, would breach the Universal Declaration of Human Rights: “There is no support for same-s-x marriage whatsoever outside of Europe and North America. Throughout Asia this is just a big no-no.”

*Read the full profile at The Power Index