A San Antonio judge is expected to name a special prosecutor to review a complaint accusing Gov. Rick Perry of coercing Travis County District Attorney Rosemary Lehmberg by threatening to veto an appropriation for her office if she did not resign after her April guilty plea on drunken driving charges.

Senior Judge Robert "Bert" Richardson's appointment will review a complaint filed by Texans for Public Justice, an Austin watchdog group, accusing Perry of bribery and coercion. The special prosecutor will determine whether the facts warrant court action or dismissal.

"We're heartened by the judge's decision," said Craig McDonald, Texans for Public Justice's executive director. "It tells us there's validity to the complaint we filed."

The group's complaint accuses Perry of bribery, coercion and official oppression.

Perry spokesman Josh Havens said the governor simply was exercising his constitutional veto authority.

"It is not Rick Perry's job to try to remove me from office," Lehmberg said. "His attempts to do that - to coerce me through a veto - I think could be illegal. I didn't appreciate it in the least, and I didn't respond."

Lehmberg, who served 22 days in jail after her April guilty plea, faces a Travis County lawsuit seeking her removal from office.

The Texans for Public Justice complaint, filed in June, contends that Perry threatened to veto funding for the Travis County district attorney's Public Integrity Unit unless Lehmberg resigned. The governor ended up vetoing $3.7 million in annual state funding for the Public Integrity Unit.

In his veto, Perry said, "I cannot in good conscience support continued state funding for an office with statewide jurisdiction at a time when the person charged with ultimate responsibility of that unit has lost the public's confidence."

The Public Integrity Unit prosecutes official misconduct and ethics violations in the state. The funding vetoed by Perry supported employees, including lawyers, investigators and forensic accountants, according to the program's director. In August, the Travis County Commissioners Court agreed to fund about $2.5 million of the unit's budget.

"The governor overstepped his authority by sticking his nose in Travis County's business," McDonald said in a statement. "A legal process is currently underway. That process alone should determine the fate of the district attorney."

Richardson, from San Antonio, was appointed to take the case because Travis County officials - including Lehmberg - said they have a conflict of interest in reviewing the complaint.

Meanwhile, Brandon Grunewald, Lehmberg's assistant district attorney, was arrested on drunken driving charges Sunday afternoon, when he reportedly rear-ended a car and injured two people, the Austin American-Statesman reported.

In a statement, Lehm­berg said her office was looking into the case and that typically, employees are not fired for first-time driving while intoxicated offenses.