Sir; re: Licensees need support (Letters, October 7) and Trading Standards dole out rough justice (Grocer Club, September 23). As a Trading Standards Officer I have been involved in the enforcement of legislation relating to illegal sales of age restricted products and have regularly used underage volunteers to attempt test purchases of tobacco, knives and fireworks. We have always adhered to published government guidelines and established best practice concerning the involvement of children. It is simply not true to suggest that the children are chosen because they look older than their real age are or are encouraged to "tart" up. For instance, for tobacco sales we will only use 11 to 14 year olds. They are never allowed to "tart themselves up" and are always instructed to give their true age if asked. If a sale does occur (which of course they do, even when the retailer is aware of their true age in some cases!) the offence is professionally investigated in accordance with the Police and Criminal Evidence Act. All the circumstances are taken into account when deciding on what action to take and a sale does not automatically result in a prosecution. This sort of work is not a lazy option for us and don't forget we have a statutory duty to enforce it. Far from doling our rough justice, my authority tries to help our retailers by providing free statutory warning notices, till prompt stickers, advice on due diligence provisions and promoting proof of age cards. The diligent retailer has nothing to fear from our work, but the minority of careless ones should take note. Paul Gander By e-mail {{LETTERS }}