She is under court order not to destroy any personal or campaign documents relating to her finances, including phone and gas bills. Prosecutors said she could face additional charges.
"We are going to look at her finances carefully to see if she reported her taxes correctly,'' McNeil said.
Other officials were named in the affidavit, including Boston Mayor Thomas Menino -- who received a phone call from Wilkerson, lobbying for new liquor licenses -- along with State Senate President Therese Murray and Boston City Council President Maureen Feeney.
The complaint alleges that Wilkerson pressured the Boston Licensing Board, the mayor and the city council to create new liquor licenses in her district. She is also accused of stalling pending legislation in the state senate, including legislation increasing the salaries of the Boston Licensing Board.
Wilkerson has represented Roxbury since first winning election in 1992, but lost the Democratic primary to Sonia Chang-Diaz last month. Wilkerson has been mounting a sticker campaign to regain her seat in the November election.
That campaign has been divisive as Wilkerson's surrogates have made flagrantly racist comments about Chang-Diaz, with one state employee working for the incumbent saying that Chang-Diaz, who is Hispanic, was "not a person of color."
Another Wilkerson supporter, Massachusetts Gov. Deval Patrick, called the charges against the senator "troubling." Menino said her arrest marked a "very sad day."
Feeney said, "this is a very disappointing day for all who are involved in public service. The people have a right to a higher standard."