For eight years, Washington pressured her Senate staff to devote weeks to drawing up guest lists that included city and state officials, creating invitations and taking money from invitees that ultimately went to Washington's campaign account, prosecutors say.
They also allegedly used taxpayer-paid computers, copiers and office supplies.
District Judge John Kessler ruled that testimony from one of Washington's former employees, Jamila Hall, was strong enough to allow the case to go to trial. In a grand jury presentment issued with the charges March 12, prosecutors listed seven current or former employees or interns, including Hall, who said they witnessed or carried out tasks to organize the fundraisers.
Washington, 68, declined comment after the two-hour hearing at Kessler's Montgomery County office. Washington, a Democrat who represents parts of Philadelphia and Montgomery County, is running for a third full term this year.
The charges against Washington include one count each of theft of services and conflict of interest, both felonies. The attorney general's office estimated the monetary loss to the state could range from $30,000 to more than $100,000.
She is scheduled for a formal arraignment May 7, just 13 days before her contested primary election against two Democratic Party challengers.
Washington's defense lawyer, Henry Hockeimer, contended that more evidence is necessary to prove that Washington oversaw a "knowing diversion" of taxpayer resources for political purposes.
For instance, he said, no paper trail supports the allegations.
He presented copies of checks that he said show that another former legislative employee of Washington's, Denise Savage, was paid with campaign funds to organize the fundraiser. He also said Hall was vague about who gave her orders, and that it seemed her labor-intensive political tasks had been ordered by Savage.
Her voice breaking under Hockeimer's cross-examination, Hall insisted that nothing happened in the office without Washington's knowledge, and that her direction to do political tasks on state time came either from Washington or Savage. In any case, Washington always approved the final product, such as the guest list, and she often checked up on fundraiser-related tasks to find out whether they had been completed.
"The understanding was, this happens during the work day," Hall testified.
Employees who said "no" were fired by Washington, Hall said.
"If you complained, you'd be fired," she said.
The investigation became public knowledge in October when agents searched Washington's offices. At the time, Hockeimer blamed a fired ex-employee, former chief of staff Sean McCray.
In the grand jury report, McCray testified that he confronted Washington about the political activities in 2012. At one point, McCray said Washington responded with a profanity-laced rebuke, saying she's the senator and she does what she wants and how she wants. "I have been doing it like this for 17 years. So stop trying to change me," Washington said, according to McCray's testimony.
After that, McCray contacted authorities, prosecutors said. He was fired Feb. 7, 2013, they said.