One might assume that, for an attorney general, considering the U.S. Constitution in his rulings is a no-brainer — a bit like a preacher considering the Bible before he writes a sermon.

He doesn't have to be told that the word of God should factor in. It's just part of the job description.

Apparently that's not the case for Texas Attorney General Greg Abbott and his staff.

At issue are two opinions in 2005 and 2006 in which the attorney general's office ruled that military veterans who weren't U.S. citizens when they joined the service no longer qualified for an 85-year-old Texas program, known as "the Hazlewood exemption" that waives college tuition.

Before Abbott's opinion, most state universities and the Texas Higher Education Coordinating Board had interpreted the term "Texas Citizen" in the Education Code to mean the veteran had lived in Texas for a year before enlisting, regardless of U.S. citizenship.

After his opinion, universities began rejecting applications from vets who were legal permanent residents but not U.S. citizens when they enlisted, including those who became citizens after enlisting.

Abbott stuck by his office's ruling, even as lawmakers and veterans advocates complained that denying benefits based on citizenship was discriminatory and opposed to the intent of the Texas Legislature.

Even Abbott's fellow Republican, Land Commissioner Jerry Patterson, urged him to reconsider. Patterson, who served in the Marines in Vietnam, declared that "no veteran should be a second-class citizen no matter where he or she was born."

But it took MALDEF — the Mexican American Legal Defense and Educational Fund — filing a federal lawsuit on behalf of several veterans for Abbott to relent. MALDEF argued that the state was violating the equal protection clause in the U.S. Constitution by discriminating against the veterans on the basis of citizenship.

A week after MALDEF asked a federal court to intervene, Abbott took the rare step of officially withdrawing his opinions.

In a letter to state Sen. Leticia Van de Putte, D-San Antonio, who originally requested the opinions, Abbott acknowledged that, through the ensuing litigation, his office had come to realize that the law, as he interpreted it, violated the U.S. Constitution. He cited the same 1971 U.S. Supreme Court case that MALDEF's lawyers cited in their lawsuit.

Now, I'll give Abbott credit for admitting he was wrong, even if he was motivated in part by the desire to avoid an embarrassing court order against the state. Texas attorney generals have withdrawn only 17 of their opinions in the past 40 years, according to Abbott's Web site.

But why didn't Abbott and his staff consider the Constitution a little earlier, before the state got sued?

The answer, according to Abbott: "We were not asked at the time, and therefore did not answer, whether such a statutory provision would be unconstitutional."

Jerry Strickland, a spokesman for Abbott, explained that the attorney general's office tries to limit its answers to the specific questions asked. No running down rabbit trails allowed. Strickland also pointed out that no one outside the office filed briefs to guide the attorney general in the opinion-making process.

"Any diversion from analyzing or considering issues outside the scope of the question asked would be inappropriate without input from others through the briefing process," Strickland said.

Really? Since when is the U.S. Constitution, the bedrock of our legal system, considered "outside the scope" of a legal question? And does Texas' top lawyer really need outside attorneys or other interested parties to file briefs to tell him what the law is?

As Van de Putte put it: "Breaking news! The AG discovers the Fourteenth Amendment!"

I would hope that the AG and his staff wouldn't wait to be sued before doing their homework.

Steve Bickerstaff, an adjunct constitutional law professor at the University of Texas, agreed.

"The attorney general's first obligation is to interpret the statute in the constitutional context," Bickerstaff said, but he added that Abbott's staff, his opinions committee, certainly wasn't the first to neglect to consider constitutional issues.

The briefing issue, however, was no excuse, Bickerstaff said.

"You don't need to have someone pose the question for you," he said. "You should do it on your own."

I'll give the attorney general the benefit of the doubt that politics wasn't at play in this immigrant-related issue. The problem seems to be poor research or incompetence or both.

The way I see it, the attorney general couldn't have thoroughly considered the question of Hazlewood without considering the Constitution. He basically took a constitutional statute and made it unconstitutional through interpretation. That wouldn't have happened if Abbott had presumed that the Texas lawmakers who wrote the law intended to follow the U.S. Constitution.

With that presumption, Abbott's staff should have assumed that Texas "citizen" meant a person who calls Texas home and Texas "resident" meant a person actually residing here.

That said, I've learned my own lesson about assumptions: don't assume the Texas attorney general is following the U.S. Constitution — unless you specifically ask him to.