An economist has a message for the federal Liberals as they try to come up with a way to price carbon that will appease 13 provinces and territories: don’t bother.

Mark Jaccard from Simon Fraser University says any price on carbon high enough to make a difference will be high enough to ensure the electoral defeat of any government that imposes it.

Jaccard says a carbon tax or carbon price would have to be about $200 a tonne before it would help Canada meet its greenhouse gas reduction targets.

That’s almost seven times higher than the highest price on carbon now charged anywhere in Canada.

Jaccard says a more effective tool would be to regulate vehicles or set emissions caps for individual industries.