There cannot be many enforcement officers who have not experienced the frustration of a lay witness getting cold feet and pulling out just before a trial. It is almost a rule of inverse proportionality that the keener the witness is to attend initially, the more likely they are to pull out as the big day creeps ever closer. Such witnesses are usually essential to the case. Their witness statement is not agreed by the defence and they will be subject to cross examination supporting the prosecution's case. This is why their court appearance may become unappealing.

What can be done if a vital witness gets cold feet? There are two routes open to the council. It can throw its hand in, and watch the smirking defendant walk away with character unblemished claiming a victory against the council. This is hardly an appealing prospect, particularly when council officers will have to deal with the individual and his friends again in the future.

The second option is to seek a witness summons from the court compelling the witness to attend. This at least gets him through the door, but it will not turn him into a competent and compelling witness. From a prosecutor's point of view nothing fills me with more horror than a reluctant prosecution witness. Most, if not all, defence witnesses are hostile to the prosecution, but at least when dealing with them I can cross-examine, ask leading questions and generally make life hard. The same is not true when dealing with a reluctant prosecution witness. I cannot cross-examine being allowed only to examine-in-chief, so no leading questions or cleverly constructed man traps. I have to be nice to them, after all, they are, in theory, on "our" side. What I cannot do, however hard I may try, is to make them sing like a canary.

A reluctant or downright hostile prosecution witness may say nothing at all. Or he may suddenly develop selective amnesia forgetting everything to do with the case, but invariably not forgetting to ask for the witness expenses claim form. Again, there is a choice. Either throw your hand in and ask for the case to be dismissed, or ask to take the witness as a hostile witness. The first choice has little to commend it - we are back to the defendant and his tales of defeating the council, but this time spiced up by descriptions of the courtroom cut and thrust.

Seeking leave to take a witness as a hostile witness is the last throw of the truly desperate. If leave is granted, usually with great reluctance by the bench, then a prosecution witness can be treated like a defence witness, and be cross examined with the full rigour of leading questions, tricks and traps. Such tactics may result in the prosecutor getting the critical evidence required to make the case, but at what cost? How many witnesses will be keen to have anything to do with the council if they believe that they will be forced into the witness box and ritually slaughtered by their own side? Word will spread and the public may be unwilling to help the council again.

More insidiously, people may become reluctant to complain to the council fearing they will be dragged to court against their will. It is far better to have as much evidence as possible given by enforcement officers, who as part of their jobs are required to support the prosecution in court. Evidence from members of the public should be restricted, where possible, to uncontentious matters that can be agreed with the defence. The remaining evidence should be in the hands of professional officers. No prosecution brought by the council, with the possible exception of death or serious injury caused at work or in private sector housing, merits forcing lay witnesses to give evidence against their will. In legal circles it is said that a reluctant witness is no witness - as true for councils as for lawyers.

Julie Barratt is director of CIEH Wales