A couple of weeks ago, back in the premature Toronto spring, a bunch of longtime journalists shared jugs of beer on a rooftop.

The talk got around to one of those surveys that measures trust in different professions. Journalists, once again, ranked way down there in public esteem with lawyers and politicians.

A colleague claimed that's because our fellow citizens don't understand what we do, why we do it or even how we do it. So all that distrust isn't our fault.

"Bullshit" growled the oldest member.

The fault, he said firmly, is entirely ours. We've allowed various base calumnies about our craft -- spread by extremists on all sides with axes to grind -- to flourish without fighting back.

Worse, being traditionally tough-minded, practical sorts, we've always been shy about talking journalistic principles and ethics, even amongst ourselves.

All of which is why I wrote my column Have We Forgotten the Media's Raison D'Être? last week.

And promised to return with the second half.

Which I now do.

I hope the oldest member approves.

"The Free Marketplace of Ideas," is the mythical place where journalists seek out and report ideas, beliefs, opinions and values bubbling away in our democratic society and expose them to the harsh and critical light of the people's judgment.

If the people decide the ideas, beliefs, opinions and values are worthwhile, the marketplace accepts them and they flourish and flower.

If the people decide the ideas, beliefs, opinions and values are worthless, the marketplace rejects them and they wither and die.

In the Free Marketplace of Ideas it is always the people who do the judging. Not journalists. Not priests. Not governments. Not courts. Not police. Not the army. Not the rich. Not the powerful.

The people.

It is both our privilege and our responsibility as journalists in a democracy to serve and guard the Free Marketplace of Ideas, to keep it open and honest for the people we serve.

We hold this privilege and responsibility as a public trust because we are the people's servants and surrogates.

We report in the people's name. We go where they cannot go. We ask questions they cannot ask.

We do these things under the traditional protection of the Free Marketplace of Ideas:

• By ancient right, the marketplace directs and authorizes journalists to be guardians of the people, watchdogs of the powerful.

• It keeps the people aware of what the powerful are doing and saying.

• It keeps the powerful aware of what the people are doing and saying.

• It's the only trustworthy, reliable link for communication between those without power and those with power.

• It's a safety valve for society. When the pressures become too strong, when society is threatened by dissent, the marketplace provides an outlet for anger, thus lessening both pressures and dangers.

• It gives the people a forum within which to seek change without violence.

• It gives the powerful a chance to act, to respond, to take action to lessen societal pressures before they explode.

The Free Marketplace of Ideas commands, therefore, that we report without fear or favour in the name of the people we have the honour to serve.

It demands of us as journalists that we are truly accountable to the people and put the people's interests before our own, any power or any cause.

It insists that as journalists our first loyalty is to the people -- and the people's right to know.

And it reminds us that, over the past 20 years around the world, roughly one journalist a week is killed in the line of duty.

Whether they recognized and admitted it or not, our dead colleagues died serving the Free Marketplace of Ideas.

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