Three con artists will spend a third more time in jail than they normally would for their crimes after a judge yesterday said he was 'depressingly impressed' by statistics showing a sharp rise in the number of street scams. District Court judge Richard Davies was urged by the prosecution to impose harsher penalties on the men as a deterrent to the rising trend for such crimes. Prosecutor Jasmine Ching submitted police figures which showed a five-fold increase in street scams last year when compared with the number of reported cases in 1997. There were 449 reported cases last year, compared to 85 in 1997. The total sum swindled from people has also risen sharply, from $3.3 million in 1997 to $26 million last year, and from January to May this year, 263 cases were reported with $14.48 million cheated out of victims, the court heard. 'We believe the statistics provide sufficient information to show the prevalence of the crime. Your Honour is therefore entitled to pass a more severe sentence than that you might originally pass,' Miss Ching said. Defence lawyer Cham Yiu-keung submitted another set of statistics which showed the number of deception cases in general, and argued these sorts of street scams could not be said to be 'prevalent'. According to the figures provided by Mr Cham, there were 2,542 deception cases in 1997 and 3,423 last year. But the judge disagreed. 'The prosecution's application has been supported by admitted statistics highlighting prevalence of these offences in the past few years,' he said. 'They are depressingly impressive . . . accordingly I found enhancement [of the penalty] justified.' The judge jailed the trio - who tried on March 24 this year to trick a middle-aged woman into buying cheap batteries at a massively inflated price - for between two years and eight months to four years. Li Yunjin, 29, and Chau Wun-shing, 47, pleaded guilty on June 16 to attempting to obtain property by deception. Judge Davies adopted a three-year starting point, reduced it to two years for their guilty plea and enhanced it by one-third to two years and eight months. Man Tin-on, 35, pleaded guilty to the same charge and one separate count of obtaining property by deception and was jailed for four years. All three were mainland visitors. In June, the court heard that victim Ting Chun-yu, who had been cheated by conmen just three days earlier, pretended to have been duped by the trio before alerting patrolling policemen. The court was told the trio had plotted to dupe Ms Ting to buy ordinary button-cell batteries, which they described as hi-tech electronic components worth $468 each and offered to sell for $300. Man used a similar ruse on March 5 in Wan Chai, successfully swindling $200,000 from another woman, Ching Shuk-hei.