Another court indicted her for negligence over a controversial rice subsidy scheme and Yingluck will face impeachment that could see her banned from politics for five years.
The two court decisions have bolstered the opposition that has been demanding Yingluck's ouster for months and accuse the 46-year-old of acting as a proxy for her fugitive brother, former premier Thaksin, who was ousted in a coup in 2006.
The EC and Yingluck-led government earlier reached an agreement to hold elections on July 20 after the February 2 snap polls were declared null and void.
