Texas Attorney General Mark A. White, who led the final legal fight that ended in the execution of Charlie Brooks Jr., today praised the courts for "great courage" in rejecting Brooks' final appeals, which he said were "frivolous" and "without merit."

White, governor-elect of Texas, said in an interview that Tuesday's execution, the first in U.S. history by injection, makes it unlikely that Woody Loudres, Brooks' accomplice in the 1976 murder of a Fort Worth mechanic, will be paroled soon.

White also predicted that fewer death sentences will be blocked on appeal because "states are doing a better job" in handling capital murder cases.

"There will be fewer and fewer legal defects," he said.

In the face of a national debate over the judicial system's handling of the execution, White said Brooks "did not have significant constitutional claims," adding that both the 5th U.S. Circuit Court of Appeals and the Supreme Court were justified in rejecting Brooks' appeals without holding a hearing on the merits of the case.

"I think it was almost to the point of summary judgment," White said. "Given everything they Brooks' lawyers said was true, so what?"

Loudres, whose separate conviction in the crime was overturned on appeal, now is serving a plea-bargained 40-year sentence and will be eligible for parole in about six years. Neither admitted pulling the trigger of the gun that killed David Gregory, the mechanic they were convicted of murdering.

White has been sharply criticized for seeking expedited appeals in capital punishment cases.

"What Mark White has done through this is manage to conduct a judicial lynching," said John Duncan, director of the American Civil Liberties Union in Texas.

White today dismissed the attacks, saying swift justice is best both for the defendant and society. He accused Brooks' lawyers of trying to "stampede" the courts in their final arguments.

"I don't think it's fair for lawyers to play time games with the courts," he said.

He said death penalty opponents should attempt to abolish capital punishment "through legislation or judicial decree, but not through judicial inaction."

On other subjects, White said:

* The withdrawal of Sen. Edward M. Kennedy (D-Mass.) from the 1984 presidential race will make it easier to assure Democratic unity after the primaries.

* He has "no plans" to endorse any Democratic presidential candidate in the primaries but will work instead to assure the kind of party unity that led to his own victory last month.

* His surprise victory over Republican Gov. Bill Clements last month is in part a message to President Reagan that "people . . . are not going to put up with his mindless approach to unemployment."

* Clements' "arrogance, indifference, insensitivity . . . and meanness" contributed to his loss.

"He abused people," White said. "And he abused me. A lot of people stood in the rain for the opportunity to say, "Quit that.' "

He also said he has "not heard one word" from Clements since Nov. 2.