A new study in Canada has shown that including agriculture in its carbon tax system did not have any impact on agriculture, despite claims to the contrary from farmers.
When agriculture was brought into a carbon tax system in the Canadian province of British Columbia in 2008, farmers there said they would be uncompetitive and trade would head south of the border to the United States or Mexico.
The Canadian government believed them, and introduced exemptions for agriculture last year.
However, Western University's associate business professor Brandon Schaufele said his study had shown the carbon tax had not affected agricultural production at all.
"So the research that my colleagues and I did was to look at whether there was any justification for these exemptions - whether the agricultural sector in British Columbia experienced any positive or negative effects with respects to international trade.
"And the punch-line is we could find no statistical evidence connecting the carbon tax to any positive or negative affects for either imports or exports."
The research was released by the British Columbia-based Pacific Institute for Climate Solutions.
The carbon tax in British Columbia only affected farm inputs - such as fertiliser and fuel - not livestock emissions which has been proposed in New Zealand.
Farmers in New Zealand are also taxed on farm inputs. Farming lobby groups in New Zealand say a tax on livestock emissions would send production overseas and that they wouldn't be able to adapt.