Who is really fiddling while the climate burns?

Ross Gittins sprayed most economists on climate change policy last weekend ("Economists fiddle while climate burns", the Sydney Morning Herald, and The Age).

Unsubstantiated assertions about motivations behind (unnamed) economists favouring a carbon tax over the emissions trading scheme (ETS) embodied in Australia’s Carbon Pollution Reduction Scheme (CPRS) dominated his piece. I can’t read other economists’ minds, but I can speak about my own motivation, and my reasons for opposing ETS in general and the CPRS in particular.

Gittins (correctly) notes a carbon tax or an ETS can deliver the same emissions reduction and price of carbon. One does so by putting a price on carbon (and forcing a reduction in emissions). The other does it by limiting the supply of permits to emit, raising the price for (scarce) permits. In principle, either approach could work.