Two key Republicans are signaling concerns about a flurry of immigration bills filed in the Texas Legislature and how far the state can go in getting tough on illegal immigrants.

A spokeswoman for House State Affairs Committee Chairman David Swinford, R-Dumas, said the lawmaker will ask the attorney general to review several bills referred to the committee.

"We don't want to pass anything out of our committee that is considered unconstitutional," Allison Scott,Swinford's chief of staff and chief committee clerk for the House State Affairs Committee, said Tuesday.

Earlier Tuesday, Speaker Tom Craddick, R-Midland, said there are questions about what the state can do and what the federal government can do.

With congressional inertia on how to confront illegal immigration, state lawmakers are giving the subject new and vigorous priority. More than three dozen bills — many filed before the legislative session even got under way — deal with immigration. The majority make it harder for the estimated 1.4 million undocumented immigrants who live in Texas.

Critics of some of the most punitive measures quickly questioned whether they overstepped authority by legislating state responses for a federal responsibility. Federal law already governs immigration policy, they pointed out.

"I see virtually no role for states in creating a patchwork of alternative approaches, and that's precisely why the founders and the Constitution have addressed it as a federal issue," state Sen. Eliot Shapleigh, D-El Paso, said earlier this year.

Some legal observers and immigrant rights advocates said they expect courtroom challenges if some bills pass.

State Rep. Leo Berman, R-Tyler, said the likelihood of a legal challenge is precisely why he filed one of the most controversial measures targeting illegal immigration.

House Bill 28 would deny state services to U.S.-born children of illegal immigrants. Berman hopes it becomes a test for the U.S. Supreme Court to interpret the 14th Amendment, which provides birthright citizenship.

Other immigration bills would tax money transfers to Mexico and Latin America, repeal a state law allowing certain illegal immigrants to pay lower tuition at state universities, enable local law enforcement to enforce civil immigration laws and require lawful presence for state licenses.

In December, Gov. Rick Perry spoke out against some immigration proposals that he called "divisive" ideas.

Though Perry didn't mention specific proposals, his comments were interpreted by some people as referring to a federal plan to build a border wall and to Berman's proposal. Scott said she didn't know if legislators had cited concerns about specific bills. She said several legislators have asked about hearing dates for their bills.

"We want to give everyone a fair hand at having their bill heard, but if it's unconstitutional we need to know that," Scott said.