To listen to Stephen Harper discuss his government's environmental record during Monday's Munk leaders' debate on foreign policy, you would hardly know that this was the same government that two years ago was awarded a Lifetime Unachievement Fossil Award at a UN climate change conference.

"For the first time we have real reduction in greenhouse gases and a real plan to reduce greenhouse gas emissions," the Conservative leader boasted during a heated exchange with Liberal Leader Justin Trudeau.

Harper also asserted that his government was "going farther and faster than the U.S." in shutting down coal-fired electricity plants, adding: "In Canada, we will have the cleanest energy sector, and doing that without imposing taxes."

To which Trudeau replied: "He talks as if Canada is an environmental steward and leader. I think he's even starting to believe his own rhetoric."

The spin

Harper's claim to environmental fame rests on several points, including the decline in greenhouse gases.

That is real, depending on when you start the count.

When Harper's government took power in 2006, GHG emissions in Canada were 740 megatonnes annually, according to Environment Canada, and by 2013, they had dropped to 726 megatonnes, a decline of about two per cent over seven years.

And, yes, it was done without raising taxes and, as Harper was pleased to point out in each of the last two leaders' debates, "for the first time in history over the past 10 years Canada has enjoyed economic growth in tandem with a reduction in greenhouse gases."

Tom Mulcair and Stephen Harper argue the Conservative government's strategy on the Keystone XL pipeline at the Munk debate on foreign affairs. 0:46

As well, his government does have a sector-by-sector plan for a 17 per cent reduction in greenhouse gases from 2005 levels by 2020.

Part of that plan, announced in 2012, involves new regulations for coal-fired electricity plants. The new regulations apply to new plants built after 2015, while existing plants built in the last 50 years have up to 2030 to close or introduce carbon capture and storage technology to reduce emissions.

"We will be the first country in the world to effectively shut down coal-fired, traditional coal-fired electricity," the Conservative leader declared.

The counter-spin

Trudeau was particularly exercised by Harper seeming to take credit for the closing of coal-fired electricity plants, since none of the closings could be traced to anything his government did.

"Mr. Harper, you do see the irony of standing here in Toronto and trying to tell people in Ontario that you somehow supported and aided the closing down on the coal-fired plants here in Ontario," he declared.

Indeed, Ontario is now officially coal-free, having closed its last coal-fired plant in April 2014, ahead of schedule.

The decision to eliminate coal in Ontario was actually made by a Progressive Conservative provincial government in 2002, and, according to Glen Murray, the province's current Liberal minister of environment, the federal government offered no help along the way.

"If the federal government wants to start taking credit for provincially funded initiatives, they could at least have the decency to make a commitment to support those initiatives in the future."

Yesterday, Alberta Premier Rachel Notley called for a "phasing out" of coal-fired plants in her province as quickly as possible. Presumably that means more quickly than the federally mandated date of 2030 for older plants.

Premier Rachel Notley on climate change and the province’s environmental policies, in remarks to the Montreal Chamber of Commerce Monday 2:00

By then, according to the CEO of TransAlta, the province's biggest coal-using utility, the share of electricity generated by coal in the province will have fallen, under the existing rules, from its current 55 per cent, the most in Canada, to 12 per cent.

The rinse

It's hard to get a clean rinse out of the climate change debate, but let's give it a try.

While it's true that GHG emissions are lower than they were when Harper took office, the only years the levels actually dropped were 2008 and 2009, during the height of the great recession.

This would explain why the Green Party tweeted during last night's debate, "Mr. Harper, if you want to take credit for the drop in emissions, you can also take credit for the 2008 global economic crisis."

What's more, GHG levels have been creeping up since 2009, and, according to the Pembina Institute, at the current rate greenhouse gases will only be 1.5 per cent lower in 2020 than they were in 2005, a far cry from Ottawa's stated goal of a 17 per cent reduction.

Nor is the phasing out of coal-fired plants over the next 15 or so years expected to make a significant difference.

Pollution from coal-fired plants represents 11 per cent of our total GHG emissions and has been falling steadily for over a decade.

The largest contributor to GHG emissions in Canada, representing 25 per cent of all emissions, is the oil and gas industry whose emissions have been rising steadily, according to Environment Canada.

The Harper government has had nearly a decade to impose regulations on the oil and gas sector, and has failed to do so.

The Conservative leader's claim that Canada has moved "farther and faster" than the U.S. in shutting down coal-fired plant is also open for debate.

Coal accounts for 38 per cent of GHG emissions in the U.S. and taking on the coal industry is politically risky.

But that is what President Barack Obama did last year when he side-stepped the Republican-controlled Congress and ordered the Environmental Protection Agency to impose strict new limits on both new and existing plants starting in 2020.

According to a study by the International Institute for Sustainable Development, Canada's new rules to control carbon pollution from coal plants will have a "negligible effect" on GHG emissions for at least the next 15 years because existing plants were grandfathered until the end of their useful life.

Scott Vaughan, the institute's president and the former federal commissioner for the environment and sustainable development, argues that "while both countries have introduced regulations, the U.S. regulations have a much deeper cut in providing real, meaningful, substantial reductions in greenhouse gases compared to Canada."

In talking about clean electricity during last night's debate, Harper claimed "we're leading the world in this sector."

Trudeau countered "we are absolutely laggards."

Neither claim is totally true, but the weight of the evidence is on Trudeau's side.