Fumo arrived at the courthouse holding the hand of girlfriend Carolyn Zinni. His attorney, Dennis Cogan, set the tone by telling reporters his client will not be talking to the press.
"First of all, you are used to this guy answering questions without inhibitions and he is under strict instructions not to answer a single question during this trial," Cogan said.
Fumo is said to be worth millions of dollars, but federal investigators alleged he was obsessed with spending other people's money to support his lavish lifestyle.
Authorities say Fumo used staffers on the Senate payroll to oversee the housekeeping and refurbishing of his 33 room Philadelphia Home.
The feds also claim Fumo and co-defendant Ruth Arnao helped stock up Fumo's shore home using money from a charity the pair had set up.
It's also alleged Fumo defrauded the Independence Seaport Museum by using its historic yachts for his personal vacations.
Once loyal staffers who have cut deals with the government are expected to testify Fumo ordered them to destroy allegedly incriminating computer files.
No jurors were picked on Monday. The process could last until Friday, and perhaps longer.
There are 220 prospective jurors.
The judge told them this trial could be up to three months long.
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