ATTEMPTS to sound reassuring can often have the opposite effect. When he spoke publicly this week, about the level of crime on O'Connell Street, the Assistant Garda Commissioner, Mr Tom King, undoubtedly meant to convince the public that the force had crime there, under control.

However, what he actually did was expose a significant gulf between the Garda view of crime levels and the citizens view, at least on one street.

There are many ways to measure crime, and it is widely accepted abroad that police records can form only part of the picture. Unreported or "hidden" crime must also be considered.

Mr King said there were 466 crimes last year on O'Connell Street, an average of just over one crime a day. He thought the media were promoting a misleading impression of the street as a dangerous place.

Shopkeepers and others who work on the street were quick to contradict him. Many said they did not report crime, but simply ejected shoplifters from their stores without telling the Garda.

It is true that the retailers have a vested interest - they want more gardai on the street, and want to promote it as a safe place for consumers.

But in the shorter term there is also the danger that shoppers will stay away as a result of adverse publicity. There is no reason to suspect that they are exaggerating crime as they witness it.

Victim surveys in other countries have highlighted discrepancies between the level of crime recorded by the police and the level of crime suffered by citizens. Invariably, victim surveys show far higher crime levels than police records.

Some types of crime - including rape, domestic violence and fraud are known to be reported less often than others. (Fewer than a third rape victims who call to crisis centres, for example, say they have reported the crime to the police Lesser crimes may also be significantly underreported.

"In Britain, rather less than half of crimes against individuals and their property get reported to the police," said Prof Michael Ho ugh, a fonder senior official in the British Home Office, who is now director of the criminal policy research unit at the South Bank University in London.

He says that while police statistics had shown a fall in crime in Britain since 1991, victim surveys had shown crime steadily rising. Victim surveys are conducted by asking representative samples of the public about their own experiences of crime. The results can then be compared with police records to show the level of "hidden" crime.

It is unlikely that any serious assault on O'Connell Street is not reported to the Garda. But there is no reason to suppose that all minor incidents are reported. And a victim of pick pocketing may not notice a missing purse or wallet until he or she is far from O'Connell Street.

THE major discrepancy between Mr Kings and the retailers accounts of life on O'Connell Street is in the area of shoplifting. Most stores on the street have security men at their doors, who know their thieves and attempt to keep them out. Those who get in and are caught stealing are often simply ejected, although some shops said they had a policy of calling the Garda.

It might be argued that those who simply eject the thieves are not doing their civic duty. But their focus is on the goods in their own shop and how they use their time. A security guard might have to spend up to half an hour holding a shoplifter at the back of the shop until a garda arrives. Who is watching the door then?

Prof Hough said yesterday that surveys in Britain also showed a discrepancy between reported and recorded crime, often because the police officers were uncertain of the reliability of the victim and doubted if a crime had been committed.

There is no suggestion that the Garda fails to record the crimes reported to it. But one shopkeeper on O'Connell Street gave the following account of an incident in her store. Two shoplifters were seen filling their pockets with goods, were caught by the shop staff and held at the back of the shop until a garda arrived. The garda instructed the two to empty their pockets, which proved full of the sort of items stocked by the shop. But unlike those on the shelves, these items had no price labels on them.

"Can you prove these were taken from your shop?" the garda asked the shopkeeper. "No," the shopkeeper admitted. "They must have taken the labels off while they were standing here."

The garda turned to, the two shoplifters and said: "Right, you can go."

Was a crime committed? The shopkeeper had no doubt she was a victim of a crime, but it is unlikely that this incident ever made it into, the official statistics.

Mr King said that, while a half million people use O'Connell Street daily, only one will be affected by a crime.

"If you put those two figures together - a half million people one way or another passing through, one person of that half million being affected by crime - I think the perception is quite different to the reality."

Is it true that every crime affects only one person? Many people, particularly the elderly, are traumatised by witnessing a crime. Many suffer indirectly when a close relative is a victim. A shop assistant who sees a colleague threatened with a syringe is seriously affected by the experience.

In the area of crime, no statistics are utterly reliable. Victim surveys, like police records, depend on how they are collated, and often on what, the collator thinks important. Anyone relying on just one set of statistics may be misled.

Summing up his view of crime on O'Connell Street, Mr King said: "the perception is quite different to the reality".

But whose perception is closer to the truth?