Luke Johnson's attack on restaurant critics in Waitrose Food Illustrated magazine may have been crude and largely inaccurate, but raising the issue of the power and responsibilities of those who pronounce upon the nation's restaurants seems to me a legitimate subject for debate.

Johnson's fire was aimed at the critics from the national papers, but many of the same issues also apply to the major guidebooks. While the judgment of a guidebook may not have a defining influence on the success or failure of a particular restaurant, it can have a huge impact on staff morale, the ability of the kitchen to recruit quality staff, and the future career prospects of the head chef.

For the major guides, this means there is a weight of responsibility on them that they can discharge only by being professional in their approach, honest and even-handed in their pronouncements and transparent about their inspection processes. Naturally, the guidebooks all have to watch their costs, and this financial discipline dictates the scope and thoroughness of the inspection process. But it's reasonable for the industry to ask for a little transparency about the procedures involved, and in particular, the regularity of inspections.

Inspection visits are a snapshot of performance, and their worth will depend heavily on the ability of the inspector to apply a set of criteria in an attempt to make the inherently subjective as objective as possible. Guidebooks should be cautious about claiming that their findings are in any way definitive. These are commercial operations with commercial pressures upon them, and despite the best efforts of those involved, it's inevitable that further up the corporate ladder there will be demands for efficiencies and cost savings.

The loser in all this can be the integrity of the guides when inspections become less frequent, inspectors less well-trained and, worst of all, when decisions on ratings are based on financial expediency rather than an honest assessment of quality.

There must be openness about inspection processes, the frequency of inspections before publication, and the experience and training of inspectors. Restaurants and consumers need this information if they are to decide what weight should be given to the pronouncements of the guides, and demanding it will help to keep them honest.