If Webster's put out a Pennsylvania edition of its famous dictionary, one of the entries might read like this: Patronage: n. 1) support, encouragement or sponsorship given by a patron; 2) the power to appoint to office or grant other favors, esp. political ones; 3) the Pennsylvania Turnpike Commission.

Before state Attorney General Tom Corbett is inevitably accused of launching another political prosecution to bolster his candidacy for governor next year, let no one forget what agency his office is investigating. For a long time, the turnpike commission has been synonymous with patronage.

Whether the political fingerprints all over the commission can be traced to individual corruption is what the attorney general's probe is meant to discover. News of the investigation became public only last week, although a hint of it had come earlier.

As the Post-Gazette reported Friday, a Pittsburgh grand jury, overseen by Mr. Corbett, is looking into whether so-called "pay-to-play" arrangements with contractors and political interference exist at the commission. Kevin Longenbach, the turnpike's former chief operating officer who was forced out in early 2007, is among those who have been questioned in the investigation.

It is too early to say where this will lead, but it isn't too early to welcome this official spotlight on the turnpike's workings. If the commission's reputation for patronage isn't enough to have raised suspicions, other red flags have been raised that cannot be ignored.

One is a civil lawsuit filed in federal court by Donald Kovac, a former turnpike labor relations manager, who alleged that he was terminated last year after refusing to reinstate a politically connected toll booth worker accused of physically assaulting a motorist.

In addition, Gov. Ed Rendell had to fire Mitchell Rubin as chairman of the commission seven months ago. Mr. Rubin's wife was convicted in a case involving state Sen. Vincent Fumo and his nefarious schemes and is himself being investigated by the FBI concerning allegations that he held a $150,000 no-work contract with the state through his private business.

This investigation can answer a lot of questions. Whatever the political advantages to Mr. Corbett, it is long overdue.

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