Largely since the Liberal Party's electoral defeat last year and the corresponding polarization of the political spectrum between the Conservatives and the NDP, the Grits have taken up the mantra of being the party of "evidence-based policy." The parties of the left and right allow their ideology to cloud their decision making, whereas only the Liberals are capable of objective thinking, so the story goes.

Even if this narrative is true, Liberals need to remove it from their refrain. Three particular reasons come to mind as to why they should do so.

The first reason is the most obvious yet perhaps the least important -- there are potentially some substantial cracks in the narrative.

Without question, the Conservative government's "tough on crime" agenda is costly. Mandatory minimums and high incarceration rates have proven historical shortcomings, to say the least. Further, the Canadian crime rate is at its lowest point since 1973.

Similarly, the NDP's claim that Canada is suffering from Dutch Disease and requires certain government-heavy medication is not completely rooted in fact. Neither the government nor the official opposition is perfect when it comes to evidence-based policy. Yet the Grits themselves have been selective in the past -- and even in the present -- with what evidence they select to back up their policy.

For instance, the Liberal Party in the last federal election argued in favour of increasing the corporate tax rate to 18 per cent from the 15 per cent it was slated to be reduced to on January 1, 2012. The argument was that increasing the rate would help generate the revenue needed to implement the Family Pack proposed in the Liberal platform. Yet the revenue generated from corporate taxes increased this year by 5.8 per cent despite the lower rate.

Here's another example. The Grits famously campaigned on a carbon tax in the 2008 election under Stéphane Dion. Yet Michael Ignatieff changed the Liberal stance when he became leader to one supporting a cap-and-trade system. See where I'm going with this? Both can't be evidence-based policy at the same time. The Grits have been more than willing to ditch evidence-based policy (i.e. a carbon tax) for political expediency in the past.

And this abuse is not just limited to the past. Liberals continue to defend the indefensible supply management system that does little more than hamper our trade prospects and increase the price of groceries.

The second reason the "evidence-based policy" refrain needs to come to a halt is because, in a sense, it's ironically the opposite of progressiveness. Instead of advancing an original and unique vision for the future of the country, the refrain in question is an implicit admission from the Grits that they're allowing the Tories and the NDP to define the contours of the political debate.

Nothing could be more reactionary. In other words, evidence-based policy is a call for moderation, and perhaps even centrism. Although these qualities are most certainly needed while in government, they are not the skills required to achieve government status.

With the two other parties squeezing the centre of the spectrum more tightly every year, what the Liberals need to find is something radical worth defending. The Charter of Rights and Freedoms, official multiculturalism and the creation of the Canadian navy are just a few historical examples of this, representing certain periods of time when the Grits were most electorally successful.

These achievements were in fact evidence-based policies, but what is important to note is that they were not billed as such. Rather, they were sold as major projects of national advancement.

Finally, the constant chest-thumping done by the Liberal Party in stating that it has a monopoly on evidence-based policy represents the one significant quality that led to the party's demise -- arrogance.

By claiming such a monopoly, the Grits are in effect dismissing the narratives of the other two parties as being not simply incorrect, but illegitimate, thus seriously offending the Canadians who voted for the other two parties last election and therefore limiting the Grits' own ability to grow their political tent.

What Liberals need to do instead is identify the major policy goals of the other two parties and succinctly communicate to Canadians that they can beat the other two parties at their own game. That means clearly identifying the Tories' shortcomings on the economic front and offering a stronger, more fiscally-responsible alternative. It also means beating back the NDP on a wide spectrum of social issues.

These two goals -- left and right -- are not mutually exclusive. It is entirely possible to have different but non-contradictory messages for two different segments of the population. For instance, a carbon tax is in itself a vote-getter on the left yet can also be sold to the right if the message is one of reduced income taxes and public debt as an intended goal, to be achieved partly thanks to the introduction of the green policy in question.

We Liberals spend too much time trying to justify our existence -- sometimes even to ourselves -- through use of the "evidence-based policy" catchphrase. Such an attitude in inherently inward-looking. It's time for Liberals -- and leadership candidates in particular -- to say what they specifically intend to do with power, not simply to announce what they claim to be. And the sooner the better.

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