Immigration Reform. Amnesty: emotional issue in immigration debate on Capitol Hill. Reagan, Hill leaders call it a fair and necessary step

Should undocumented aliens in the United States be granted ``amnesty''? Should millions of aliens be given American citizenship, even though they have slipped into the US illegally? The American public doesn't like the idea. In a series of polls spanning 1977-84, Gallup found that a consistent 52 to 55 percent of the voters opposed amnesty. About 38 percent favored it.

Even so, President Reagan and many leading members of Congress have insisted that amnesty is the fairest, most expeditious way to resolve the mounting crisis along the US border with Mexico.

This fall on Capitol Hill, two major immigration reform measures -- the Simpson bill in the Senate and the Rodino-Mazzoli bill in the House -- will tackle this issue. Both call for amnesty.

The bills have put Congress on a collision course with public sentiment, and this could help to spark one of the most emotional fights in the immigration debate now warming up on Capitol Hill.

Critics of amnesty, such as Rep. Hal Daub (R) of Nebraska, make these points:

Amnesty rewards law-breakers. Why should illegal aliens become citizens when millions of legal aliens are awaiting their turn to enter the US?

Amnesty could be costly. Public expenses for education, welfare, and other needs could soar. Who will pay?

Amnesty sends the wrong signal. If the US grants amnesty once, it may do it again. Other people will be encouraged to sneak across the border.

Amnesty could set off a US population explosion. There may be 6-to-12 million illegal aliens today in the US. Once they are citizens, they could legally bring in millions of their relatives.

Amnesty could lead to resource problems in the Southwest. Most new immigrants would be expected to settle in California and other Western states. Water shortages could result.

Amnesty takes pressure off other nations to solve their problems. Mexico, for example, has severe population problems. As long as Mexico can use the US as a ``safety valve,'' there is little pressure to hold down its population growth.

Amnesty could damage the US economy. The US is moving toward high technology -- ``computerization and robotization,'' in Mr. Daub's words. Absorbing large numbers of unskilled workers from abroad would require the US to develop a different type of economy.

But amnesty has its defenders.

Sen. Alan K. Simpson (R) of Wyoming says if the US doesn't permit amnesty, a massive roundup of millions of people would be required, with forceful deportation. Many of those who would be deported have lived here for years, have jobs, and have children who were born in the US. Senator Simpson says he couldn't support their deportation.

Some economists, such as Julian Simon, also argue that illegal aliens have made a positive contribution to the US. They harvest many of the crops, work in restaurants, clean hotels, assemble computers, and make many other contributions to the US.

Without low-cost, hard-working alien labor, some US industries, such as clothing, would have a difficult time surviving, some economists contend.

Rep. Bill Richardson (D) of New Mexico defends amnesty as ``a practical decision that is consistent with effective law enforcement. The failure to include [an amnesty] program would aggravate conditions.''

Even advocates of amnesty, however, differ on some points. Senator Simpson's original bill this year called for amnesty only after the US had regained control of its borders. That was later changed to permit amnesty after no more than three years. The Rodino-Mazzoli bill calls for amnesty concurrent with the imposition of employer sanctions. The sanctions would make it unlawful for businesses to hire illegal aliens.

Another key difference: the Rodino-Mazzoli bill grants amnesty to aliens who were in the US before Jan. 1, 1982. The Simpson bill gives amnesty only to those who were here before Jan. 1, 1980.

That small difference makes a huge difference in numbers. The Senate bill, according to an estimate by the Congressional Budget Office, applies to only 17 percent of aliens now in the US. The House bill would apply to 40 percent.

Obviously, not every eligible alien would apply for citizenship. Some have strong ties to their homelands. Some would not be able to pass the required English-language or US history tests.

The Congressional Budget Office estimates that about 60 percent of those eligible would eventually pledge allegiance to the red, white, and blue. Third of four articles. Next: Who pays?