Let's be clear: The problems facing the Travis County District Attorney's Public Integrity Unit trace directly back to the Travis County district attorney, Rosemary Lehmberg.If not for her stumbling-drunk driving in April and her obnoxious behavior after she was arrested and jailed, the unit would not be in the mess it's in today. That said, Gov. Rick Perry has shown a shocking degree of political opportunism (even for him, a consummate professional politician) by using his line-item veto to cancel the Public Integrity Unit's $7.6 million in state funding for 2014-15, blaming Lehmberg.In his veto message released Friday, the governor cited “the otherwise good work (of) the Public Integrity Unit’s employees” but said he yanked the funding because “the person charged with ultimate responsibility for that unit has lost the public’s confidence.”Then came a pearl of Perry logic: “This unit is in no other way held accountable to state taxpayers except through the State budgetary process,” he said, so he pulled the appropriation.But the governor had already declared the unit’s work “good.” For what else should it, not the DA herself, be held accountable?The Public Integrity Unit has work to do only because it’s in Austin, the seat of state government. Legal tangles involving state officials, many of them ethics cases, are filed there.The unit is investigating millions of dollars in grants given by the Cancer Prevention and Research Institute of Texas without proper vetting to entities run by closely connected individuals. In 2010, the unit’s work led to the conviction of former House Speaker Tom DeLay, R-Sugar Land, on money-laundering charges. DeLay is appealing the case.Perry pushed for Lehmberg’s resignation after her drunken-driving arrest. She pleaded guilty and spent three weeks in jail, but she wouldn’t resign.Lehmberg is a Democrat, as are the majority of voters in Travis County who put her in office. If she were to resign in midterm, Perry could appoint someone to take her seat.Its Democratic base has long made the Public Integrity Unit a thorn in the side of Republicans, although they’ve not been able to show that its prosecutions on the whole have been politically biased.Perry has every right to pursue his partisan goals and those of his party. But his funding veto is extreme, unjustified and inappropriate.