ILLEGAL immigrants required as witnesses in court cases will no longer be held unduly in jail, but will be released into the community under a plan mapped out by the Government. Only in exceptional circumstances will the courts order that they be kept in detention - a move that was rejected by police involved in the working group responsible for devising the scheme. The fears of police and prosecutors are that once released into the community, many of the witnesses will remain at large and fail to turn up for court. There are also legal concerns that many witnesses will play down the strength of the evidence they have to offer because if they are considered to be important witnesses they have a higher chance of being detained. All juveniles will be placed in the care of the Social Welfare Department rather than placed in Victoria Prison under the proposals. Under the findings and recommendations which have been endorsed by Governor Chris Patten and will go before a Legislative Council panel on Thursday, illegal immigrants who are witnesses in court cases will still be held under the existing section of the Immigration Ordinance, which allows their detention for 28 days. After that, they will be released on their own recognisance with reporting conditions and the Judiciary has agreed that all efforts will be made to bring trials on as soon as possible. People could only be detained beyond the 28-day period if the courts were convinced they were key witnesses or there were other relevant circumstances. Applications that they be further detained must be made to the courts every 21 days. The working group did not consider whether illegal immigrants should be given legal representation, but the Judiciary gave assurances that those held in detention would be there for the shortest time possible because all efforts would be made to expedite trials. Those already in detention waiting to give evidence in forthcoming trials will have the issue of their detention reviewed as they come before the courts according to the 21-day reviews. Earlier this year the Government admitted it was wrong in detaining two illegal immigrant girls for nine months and Governor Chris Patten ordered the Secretary for Security, Alistair Asprey, and the Attorney-General, Jeremy Mathews, to examine the issue and produce a report. Both girls, one aged 14, the other, 17, were transferred into the care of the Social Welfare Department and have since been released into the community. ''Of course, one of our worries is that people released by the courts will disappear into the community and not turn up for court,'' a government official said. ''But what can we do? We are in trouble if we detain people who are not criminals and we are in trouble if we release them into the community.'' The proposals do not make any changes to Section 32(4) of the Immigration Ordinance, which allows the detention of people for up to 28 days who may be able to assist with inquiries or act as witnesses. The section is considered a crucial part of the Government's crackdown on local employers exploiting illegal immigrant labour. The working group, which delivered its findings to the Governor last month, involved officers of the Security Branch, the Attorney-General's office, immigration, police, the Judiciary and the Social Welfare Department. It is understood that not all members of the group were in agreement with the recommendations made to Mr Patten in their paper. At the end of June, a total of 20 people were being detained under Section 32(4) of the Immigration Ordinance. The Director of the Society for Community Organisation Ho Hei-wah said the changes were a step in the right direction but ''still unacceptable''. ''The Government is breaking all laws of human rights by detaining these people who are not criminals,'' Mr Ho said.