Immigrant advocacy groups are raising concerns that a U.S. Senate reform bill may not benefit foreign workers as promised. In Miami, VOA's Brian Wagner reports that pro-immigrant leaders fear the measures may place undue burdens on mostly Hispanic immigrants and their families.

Several pro-immigrant groups are speaking out about the Senate bill that seeks to address problems in U.S. border security and the status of some 12 million illegal immigrants in the country.

President Bush and supporters of immigration reform say the bill is needed to help fix a broken immigration system. Proposed measures include tougher border security, a guest worker program, and a path for undocumented workers to gain legal status in the U.S.

Lawmakers have engaged in fierce debates about the proposals, especially measures that would change entry requirements and visas for foreign workers, and require undocumented workers to return to their home countries to apply for a green card, or residence permit. A vote on the bill is expected within weeks.

Douglas Rivlin, director of communications for the pro-immigrant National Immigration Forum in Washington, says proposed changes to visa policy mark a reversal of earlier U.S. policy. "What the Senate is debating is a pretty radical departure from the way America has done immigration for the last 40 years or so," he said.

Rivlin says U.S. visa policy has long emphasized an immigrant's ties to the United States through family or work connections. He says a proposal to score visa applicants on criteria such as English-speaking ability, education or profession may end up favoring skilled workers over those with few or no skills. The result could be a shortage of workers for farming, construction and other jobs that are currently filled by many undocumented immigrants.

Leaders of the Roman Catholic church in Miami have taken issue with the Senate bill for failing to emphasize the importance of keeping migrant families intact. Randy McGrorty, director of Miami Catholic Legal Service, called on lawmakers to reconsider proposals that would grant visas to guest workers but not to their spouses or children.

"It has been a cornerstone of our immigration policy since the 1920s that families get preference to reunify. That needs to be rethought because that policy would go away if these new proposals are enacted," he said.

Another controversial measure under consideration by the Senate is the creation of two-year renewable visas for foreign guest workers. Wednesday, senators voted to halve the number of proposed visas under the guest worker system, cutting it to 200,000 because of uncertainty about its potential impact.

Several labor unions, whose members include many Hispanic immigrants, have said the guest worker program would create a so-called underclass of workers with few legal protections. Michael Wilson, vice president of the United Food and Commercial Workers Union, says the temporary status of guest workers makes them vulnerable to being underpaid, injured on the job, or being forced into debt by their employers. He spoke Thursday to members of the House of Representatives, who are considering their own immigration reforms.

"To suggest that a new guest worker program can be constructed with adequate workplace protections is disingenuous and flies in the face of history and current practices," he said.

President Bush has defended the Senate proposal as a way to reduce illegal immigration and improve legal immigration opportunities for foreign workers. In a news conference Thursday, he said he understands some of the immigration measures are controversial.

"But if you're serious about securing our borders, and bringing millions of illegal immigrants in this country out of the shadows, this bipartisan bill is the best opportunity to move forward," he said.

President Bush has said he would like to sign a comprehensive immigration reform before the end of the year.

Senators are continuing to debate the reforms and may make additional changes to their bill before it reaches a possible vote in coming weeks. If approved, it would have to be reconciled with a possible House bill.