The Texas Tribune decribes the impact of the cut here.
Click here for the governor's message on all line item vetoes. This is the part that relates to the Public Integrity Unit.
Click here for information about the Public Integrity Unit from the Texas Tribune.Article IV - The Judiciary
Judiciary Section, Comptroller's Department
D.1.4 Strategy: PUBLIC INTEGRITY UNIT, $3,742,829 $3,830,597
TRAVIS CO & UB
Public Integrity Unit, 53rd Judicial District.
Despite the otherwise good work the Public Integrity Unit's employees, 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. This unit is in no other way held accountable to state taxpayers, except through the State budgetary process. I therefore object to and disapprove of this appropriation.
And here for a list of stories related to the unit from the same source.
The Texas Republican Party has sought to eliminate the unit for many years. It highlights the political conflict that exists between the liberal leaning elected officials of Austin and Travis County and the more conservative officials elected state-wide. The unit had investigated Tom Delay among other prominent officials. The current DA's arrest may have simply given the governor cover for accomplishing a goal he has sought for some time. If she resigns, he gets to appoint a replacement - which woudl certainly be a Republican less anxious to investigate the governor.
Here's a story about a past attempt to get rid of the unit in 2011, and to remove the authority to investigate fraud from the Travis County DA's office to the Attorney General's office.
Texans for Public Justice have filed a complaint about the governor's veto, but the complaint was filed with the Public Integrity Unit, which creates some obvious problems. They argue that the governor's actions overstepped his authority.