The leader of Texas' largest business group said Wednesday that Gov. Rick Perry's new election promise to crackdown on employers who hire undocumented workers would be unfair and untenable.

"Our view is that this is a federal issue," said Bill Hammond, executive director of the Texas Association of Business, whose members include some of Perry's largest campaign donors.

In an online campaign speech launching his 2010 re-election bid Tuesday, Perry reversed his previous stance on employer sanctions and said he would press lawmakers to enact criminal penalties for businesses that knowingly hire undocumented workers.

"Texas jobs should be held by folks who are here legally," Perry said.

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During his 2006 campaign, Perry said he opposed using state laws to punish employers who hire undocumented workers.

The change was one that Perry's GOP rival, U.S. Sen. Kay Bailey Hutchison, was quick to pick up on.

"Texans deserve a governor they can trust won't change their positions on critical issues like illegal immigration to suit an election," said Hutchison campaign spokesman Joe Pounder.

Campaign spokesman Mark Miner said Perry's focus in recent years has been securing the Texas-Mexico border since the federal government hasn't done so.

Perry has long said border security must come before immigration reform. In 2007 and again 2009, lawmakers dedicated about $100 million to border security efforts, at his request.

"Now, at this point, the federal government has fallen down on this issue, so he's taken a stronger stance" on employer sanctions, Miner said.

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But Hammond said it would be unfair to go after Texas employers because they have no way to accurately determine whether workers present false documents.

The federal government's e-verify program that is meant to let businesses check on their workers' status isn't always right, he said, and most employers aren't forensic experts who can judge the authenticity of documents workers present.

"Our members, and employers in Texas in general, want to obey the laws. They make every effort to do that," Hammond said.

In 2007, Hammond helped launch the group Texas Employers for Immigration Reform specifically to lobby against state-imposed employer sanctions.

Houston homebuilder Bob Perry, who is not related to Gov. Perry but is one of his top financial supporters, is a member of the employer group. Other large Perry contributors who have joined the group include El Paso developer Woody Hunt and San Antonio health care equipment magnate James Leininger.

The employer group has urged state lawmakers to leave immigration laws to Congress.

But Hammond said the governor's new position on state employer sanctions wouldn't affect the association's support for Perry.

"We will continue to maintain our principles and let him know directly or indirectly exactly how we feel on this issue," Hammond said.

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Other states — like Arizona and Oklahoma — have already implemented policies that punish businesses that hire undocumented workers.

Luis Figueroa, legislative attorney for the Mexican American Legal Defense and Educational Fund, or MALDEF, said states are creating a hodgepodge of immigration laws that make it tough for businesses to operate.

"It doesn't make a lot of sense in this economy to create more regulations that make it harder for employers to hire people and do business here," he said.

Jim Henson, director of the Texas Politics Project at the University of Texas, said Perry's new get-tough rhetoric would likely appeal to the Republican primary voters but probably wouldn't hurt him with his political deep pockets.

"You campaign one way, then when you're governing, the math, the calculus, is different, and everybody knows that," Henson said.

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