Fewer illegal aliens caught at US border. But interpretations vary on why the drop

Is the new immigration law working? Arrests of illegal aliens along the dusty United States-Mexican border have dropped dramatically this summer.

Immigration authorities attribute much of the falloff to the employer-sanctions provision of the law, which is intended to thwart the flow of illegal immigrants to the US by taking away their main reason for coming, plentiful jobs.

But others argue that detentions are down for different reasons. They see the law having little effect on the hiring practices of US companies, and thus in sealing the porous 1,900-mile border.

``I don't see any indication that there are fewer people coming in,'' says Anna Garcia, a researcher at the University of California San Diego.

The varying interpretations, together with wide fluctuations in arrest statistics at the border, underscore the difficulty of trying to fathom the impact of such a massive change in the nation's immigration policies almost two years after it was signed into law.

``It is still very unsettled,'' says Doris Meissner, a senior associate at the Carnegie Endowment for International Peace. ``There is a period of substantial readjustment going on.''

What is clear, for now, is that the number of aliens being arrested along the border - usually a gauge of the level of illegal immigration - is substantially down after being up the first five months of the year. US Border Patrol agents nabbed 36 percent fewer aliens in August than they did the during that month a year ago. Forty-two percent fewer were arrested in July and 31 percent in June.

The declines were sharp enough that the totals for the first 11 months of fiscal year 1988 are down 16 percent over 1987, despite earlier increases.

INS officials say the drought and earlier reports of a surplus of migrant workers may have kept undocumented aliens from coming north to seek work in agriculture this year. Some Mexicans may have stayed home because of the recent elections there.

Nevertheless, federal officials argue that at least part of the drop is because of the sanctions provision of the sweeping new law, which for the first time holds employers liable for knowingly hiring illegals.

``There is no doubt the law has impacted to a degree,'' says Harold Ezell, INS Western regional commissioner.

Although the Immigration Reform and Control Act was signed into law in November 1986, tough enforcement of the sanctions against employers did not begin until June of this year. So far, the agency has fined 320 companies for a total of $1.8 million.

One major user of illegal labor, agricultural growers, remains largely exempt from the sanctions. The INS won't go after them until Dec. 1, the same time a special program offering legal status to alien farm workers ends. The first phase of a more general amnesty program, another key part of the immigration reform law, ended May 4.

With the crackdown on growers, coupled with the addition of 1,100 more agents along the border by mid-1989, federal officials say they will be able to reduce the flow of illegals into the US substantially.

Others are dubious. Surveys of immigrant-dependent businesses in southern California done by the University of California San Diego suggest loopholes in the law may undermine its effectiveness. They show some illegal aliens are using fake documents to get hired - and some employers are knowingly accepting them.

Under the law, employers must verify a job applicant's legal status to work. But they don't have to determine the authenticity of documents presented. Thus specialists like Anna Garcia believe there will continue to be low-wage jobs available for aliens - and they will continue to trek north.

In Tijuana, research by Jorge Bustamante at the College of the Northern Border indicates that there has not been a huge drop in the number of migrants trying to enter the United States. Researchers there try to gauge the volume of illegal migration by taking pictures and counting the number of people who gather daily at a major staging area for illegal crossings.

Some analysts suggest that the US Border Patrol's arrests are down, not because of any drop in illegal entries, but because fewer agents are working the border. While INS officials concede that some officers have spent time on other duties, even some independent analysts say this would not be enough to account for a general drop in arrests since 1986.

David North, a respected researcher at TransCentury Development Associates, sees three reasons for the decline in apprehensions: the sanctions, the glut of farm workers earlier this year, and the large pool of aliens seeking legalization under the amnesty programs, some of whom can get papers allowing them to cross legally.