HARRISBURG - It was business as usual. Everyone did it. Working on politics during the legislative day was just a part of the daily grind in the state Capitol.

And though State Rep. Bill DeWeese was the top House Democrat during much of the time it went on, he was merely "a figurehead," leaving the day-to-day legislative operations to others.

So testified William G. Chadwick Jr., a former prosecutor and state inspector general, and the first witness called to the stand Monday morning to begin DeWeese's defense.

DeWeese, 61, of Greene County, is charged by the state Attorney General's Office with directing and condoning political activity by state employees who were on the taxpayers' dime and time.

Chadwick, once a top deputy in the Philadelphia District Attorney's Office, told jurors that DeWeese had hired him in the wake of the so-called Bonusgate scandal in 2007 to investigate corruption in the House Democratic caucus and craft a plan to correct it.

"Bill [DeWeese] gave me complete license to do whatever needed to be done . . . to ensure integrity," Chadwick told the jury of seven women and five men.

And that, noted Chadwick, was not the norm.

Over an hour on the stand, the prosecutor-turned-consultant gave an inside look at the hysteria that gripped the Capitol after then-state Attorney General Tom Corbett began looking into the legislature's bonus scandal in 2007.

There were reports of massive document-shredding sessions in the Capitol, as well as people deleting e-mails. "It was out of control," Chadwick testified.

He said he and his team were tasked with complying with prosecutors' subpoenas for a list of documents so extensive it required poring through hundreds of thousands of pages.

Many of those e-mails were incriminating, he said, and were immediately turned over to prosecutors. They also led to the firings of several House Democratic employees, including DeWeese's former chief of staff, Mike Manzo.

Chadwick maintained that it was Manzo, together with former State Rep. Mike Veon, a Democrat from Beaver County, who ran the day-to-day operations. Veon was convicted in the Bonusgate case and is serving prison time. Manzo - who was a star prosecution witness against DeWeese last week - has pleaded guilty and has not yet been sentenced.

"DeWeese was an outside guy - he was never there," Chadwick told the jury. "Veon, on the other hand, had an appetite and an aptitude for management."

So strong was Veon's power that even after being ousted by voters in 2006 from his legislative seat, he and Manzo still tried to direct the House Democratic caucus' daily operations from the Capitol's steps, Chadwick testified.

Prosecutors sought to portray Chadwick as someone who was hired by, and answerable to, DeWeese - at considerable public expense. Chadwick's consulting firm was paid roughly $1.7 million for its work over the course of almost two years.

Yet Chadwick, on cross-examination, managed to deftly inject points that could help DeWeese, including the contentions of some critics that the attorney general's probe had political overtones of its own. At the time it was launched, Gov. Corbett, a Republican, was attorney general. Corbett has repeatedly called such suggestions baseless.

Chadwick brought up Corbett's name during testimony - to swift objections from prosecutors.

Through it all, the jury listened intently, with some jurors leaning forward in their chairs and taking copious notes.

In many ways, Chadwick was an unusual witness. As a former prosecutor, he understands the nuances of courtrooms and juries. And as a former DeWeese consultant who spent two years immersed in the inner workings of the House Democratic caucus - and in almost daily contact with the Attorney General's Office - he came armed with knowledge available to few other potential witnesses.

Chadwick spent more than 15 years in the Philadelphia District Attorney's Office, where he became top deputy to then-District Attorney Ronald Castille, now the chief justice of the state Supreme Court. In the early 1990s, Chadwick was appointed inspector general under then-Gov. Robert Casey and later served in Gov. Tom Ridge's administration.

Chadwick now runs a Washington-based consulting firm that advises corporations, nonprofits, and government entities on ethics and other matters, and in that role he has become something of an investigator-for-hire. In 2010, he was hired by Castille to conduct an outside investigation of the state Supreme Court's failed Family Court building deal in Philadelphia. Castille also tapped him to assist in a review of Philadelphia's criminal-justice system after an Inquirer series found the city's courts in crisis and to conduct an inquiry into alleged favoritism by Philadelphia Traffic Court judges.

Monday was the first day of DeWeese's defense, which is expected to run most of this week. Bill Costopoulos, DeWeese's attorney, has said he expects to call between 40 and 50 witnesses, most likely including DeWeese.

Also testifying Monday were several witnesses who said DeWeese routinely directed them and other staffers to make sure they took personal leaves if they were to perform campaign work during the legislative day.

DeWeese's defense has been that election work did take place during legislative hours, as prosecutors allege - but that the legislator directed his staff to do such work on their lunch hour, or using vacation, compensatory, or personal time.

Contact staff writer Angela Couloumbis at 717-787-5934, acouloumbis@phillynews.com, or @AngelasInk on Twitter.