Controversial advertising holds a mirror up to society. It can unite us in laughter or outrage, spark debates that shape our beliefs—and sometimes expose our political differences.

But where do lines of acceptability or offensiveness get drawn? Earlier this year the New Zealand Advertising Standards Authority (ASA) announced the most complained about ads ever.

Categories ranged from political advocacy to household products. And the most complained about spot belonged to Hell Pizza's "Lust condom" mailers. The brand's "Hell Crossed Buns" billboard came in third.

This is not surprising, given the brand is often in the headlines for its provocative campaigns. Controversy is clearly part of the marketing strategy.

But while multiple complaints might suggest widespread public criticism, our research wanted to test the changing relationship between religious belief and advertising standards: what offends New Zealanders, what pushes the boundaries, and when does an ad cross the line of "acceptable" controversy?

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