South Korea's beleaguered president, Park Geun-hye, refused to testify at her impeachment trial Tuesday, days after she publicly denied allegations of corruption.The country's Constitutional Court was forced to delay the start of oral arguments because of Park's absence. She was asked to testify on Thursday, according to The Associated Press, when several of her current and former aides are scheduled to testify.The AP says court "cannot force her to appear but can proceed without her if she refuses twice to appear at the hearings."A lawyer for Park, Lee Joong-hwan, told reporters that the president wouldn't attend future hearings "unless there are special circumstances," South Korean news agency Yonhap reports."Citing law, he also said an impeachment trial is meant to proceed in the absence of the defendant," the news agency added.Last month, South Korean lawmakers voted 234 to 56 to impeach Park. As NPR's Elise Hu has reported, prosecutors say Park "conspired in a multimillion-dollar extortion scheme, led by her close friend and spiritual adviser, Choi Soon-sil" and that Choi "enjoyed extraordinary power to make decisions in state affairs, despite holding no official position."The court will decide whether to uphold the impeachment vote.Elise reported last month that: