"Democracy has died in Thailand today, along with the rule of law. That move to destroy me is still ongoing and I face it now," she said in a statement posted on her official Facebook page following her impeachment.
Ms Yingluck, the kingdom's first female premier and the sister of former leader Mr Thaksin Shinawatra, was toppled from office by a controversial court ruling shortly before the army staged a coup in May.
She faces impeachment on January 23 by the junta-picked National Legislative Assembly over her administration's populist rice subsidy programme, which funnelled cash to her rural base but cost billions of dollars and inspired protests that felled her government.
The guilty verdict will bring an automatic five-year ban from politics and risks enraging her family's 'Red Shirt' supporters, who have laid low since the coup.
Speaking before the hearing January 22, Mr Jatuporn Prompan, chairman of the Red Shirts, cautioned against street protests on his television show, after noting signs he believed would "lead to impeachment".
"From tomorrow, we will see more clearly... If we are not patient, Red Shirts will be accused of being responsible for bad things," he said on Peace TV.
"It is not over on the 23rd, tomorrow is not the end. Time will tell... We have to be patient," Mr Jatuporn urged his viewers.
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