LUIS ESTRADA fled El Salvador to avoid the tumult of war and to be reunited with his mother in the United States for the first time in eight years. Instead of leading a happily-ever-after existence in ``el norte,'' however, the slight 16-year-old was arrested while slipping across the US-Mexican border - and spent the next 17 days in detention. Luis (not his real name) is one of at least 100 alien youngsters who are detained at any given time by the United States Immigration and Naturalization Service for illegally entering the country. They are the source of an enduring dispute between the federal agency and immigrant-rights groups over conditions in the detention facilities and how children should be handled.
Critics contend that many of the centers run by the INS or by contractors for the agency carry out practices - such as putting children into quarters with adults - not allowed under state and federal standards for most juvenile lockups.
At the same time, the rights groups disagree with an INS policy, adhered to with different strictness in different parts of the country, which provides that detained minors may only be released to parents or legal guardians while awaiting deportation hearings.
The critics contend that by not turning the young detainees over to relatives or interested third parties such as religious groups, the INS unnecessarily forces many of the children to languish in detention centers for weeks and even months.
INS officials counter that the facilities are properly run, and minors are detained only for brief periods. They contend that the agency's selective-release policy protects the best interests of the children. ``The question is protection of the children,'' says Bill Odencrantz, counsel for the Western regional office of the INS. ``We cannot just release a four-year-old to any person who walks in the door and says, `I want the kid.'''
But INS officials concede that detaining children who have entered the US illegally is a delicate issue and one that has become a growing problem in recent years. As the volume of illegals coming across the border reached unprecedented proportions in the mid-1980s, the number of children trekking north - mostly from Mexico and Central America - likewise increased.
Since passage last fall of the US Immigration Reform and Control Act, the number of minors arrested has declined, as have detentions of aliens in general. In the Western region, where most of the minors are detained, INS officials say 60 to 75 children are in custody on any given day, vs. 125 last fall. Most of the rest are in facilities in Texas.
``It is a serious problem,'' says Alice Bussiere of the National Center for Youth Law in San Francisco. ``I think it has been overlooked because it is so easy to forget.''
A chief concern of critics is the practice of turning over minors, with few exceptions, only to parents and court-appointed guardians. Although the policy has been adopted by the INS nationwide, local administrators have leeway in how they carry out the stricture. It has been most rigidly adhered to in the Western region, INS officials say, where the policy was initiated.
Officials in the Western office, which is headed by Harold Ezell, say they have a ``moral responsibility'' not to release children to just any person or group that comes in. At the same time, there is concern of legal liability if something should happen to a minor while in the custody of someone other than a parent or legal guardian, who, the INS says, are best equipped to care for the children and guarantee their appearance at deportation hearings.
Critics of the policy say that problems arise because a sizable number of the children are either war orphans or do not have any parents in this country. Most affected are children from Central America, since most Mexican children are simply deported back across the border.
Some of the Central American children have parents in the US, but many of the parents are here illegally themselves. Thus, they subject themselves to deportation by coming in, though most eventually do this rather than leave their children with the INS. In addition, critics contend that the process of providing a court-appointed guardian can be costly and time-consuming and results in confinement of too many children for too long.
``A lot of these children stay in these places for months,'' says Geri Silva, head of the Los Angeles chapter of the Equal Rights Congress, a civil rights group.
INS officials, for their part, say that the average detention period for children in the Western region is about seven days - and that it is exceptional for children to remain in custody for weeks or months.
One who did is 17-year-old Carlos (his last name has been withheld at his lawyer's request). Carlos, a former seminary student, left Guatemala last year to be reunited with his mother in the US. He came because there was no one left in Guatemala to take care of him. His father is missing and presumed dead.
Arrested while crossing the border, Carlos was detained for six weeks. He was released only after his mother, who is also an illegal alien, came forward. Carlos and his mother are seeking political asylum.
``It is very bad,'' he says of his confinement. ``It is not good. That's all.''
Critics say conditions vary widely at the half-dozen or so detention facilities used for the youths. They laud Casa San Juan, a center operated by the Roman Catholic Church in San Diego. But they are sharply critical of some of the INS-run facilities, such as a staging center in Chula Vista, Calif., where aliens are supposed to be held only briefly.
In addition to commingling children and adults, critics charge the agency with heavy-handed security checks, restrictive visitation practices, and not providing proper recreation and education for the youths.
``There is no question that this type of detention really deteriorates a child,'' says John Hagar, a lawyer here with the American Civil Liberties Union (ACLU).
INS officials deny any rough treatment and say what few unaccompanied children there are in the facilities are not generally mixed with adults, except in outdoor recreation areas. They also contend that the agency bends over backward to try to reunite children with their families and see them released. ``I can't be releasing these kids not knowing where they are going,'' says Don Looney, assistant Western regional commissioner. ``We don't have the staff to do home studies.''
To press their case, the ACLU and immigrants' rights groups are pushing ahead with a lawsuit against the INS. This week they won what they consider a partial victory: A federal judge here issued a ruling that may lead to more minors being released to close relatives.
Meanwhile, a group of church and immigrants' rights groups in California has launched a petition drive to try to spur changes.