Smith declined further comment on the plea agreement, and disclosed few details of the alleged misdeeds.
The prosecutor did say that between 2006 and 2010, Mellow and his advisers tapped state-paid staffers to raise money and perform other tasks for Mellow's reelection campaign, and for the campaigns of candidates he supported.
Mellow, Smith said, demonstrated "willful blindness" to the illegal activity and as a public official "had a duty to refrain from the improper use of Senate resources and staff."
Sal Cognetti Jr., Mellow's attorney, declined comment on the charges and the plea deal - except to say that Mellow, for two years, "has been fighting a war on two fronts: the first concerns his health, the second relates to an investigation by the federal government."
Because he "cannot continue to wage battle on both fronts," his attorney said, Mellow has decided "to resolve the dispute with the federal government."
Cognetti would not elaborate on Mellow's health.
Mellow spent more than 20 years as the Senate's top Democrat, and was part of what is now a nearly extinct political leadership group for whom deal-making was as much a part of the job as policy.
He shared power in Harrisburg with the likes of former Democratic State Sen. Vincent J. Fumo - now jailed on federal corruption charges - and, like Fumo, was known for working to ensure that his home territory got a slice of each pie. For Fumo, that territory was Philadelphia; for Mellow it was Scranton and northeastern Pennsylvania.
The charges made public Thursday did not mention controversy that erupted in 2009 over tens of thousands of dollars in rents paid out of state funds for one of Mellow's district offices.
The Inquirer reported in 2009 that Mellow had charged taxpayers more than $200,000 over seven years for renting an office near Scranton in a building co-owned by his wife at the time - and later by himself. Over time, people with ownership stakes in the building also included a longtime Mellow aide.
State law bars public officials from using their posts for financial gain for themselves or their immediate families.
At the time, Mellow said he had done nothing improper.
Soon after, though, the FBI interviewed Mellow's ex-wife about the matter. Mellow announced his retirement in early 2010, saying he wanted to spend more time with family.
That summer, federal agents raided his home and district office. Authorities said they were investigating "alleged illegal activities."
Thursday's charges of campaigning at state expense had an all-too-familiar ring. Since 2007, the state Attorney General's Office has brought similar charges against 25 people in three probes, including the so-called Bonusgate and Computergate cases.
Those prosecutions led to prison terms for former top House Democrat Mike Veon of Beaver County and former Republican Rep. Brett Feese of Lycoming County. Former House Speaker John Perzel (R., Phila.), who pleaded guilty, and Rep. Bill DeWeese (D., Greene), who plans to appeal his conviction, are awaiting sentencing.
Contact Angela Couloumbis
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