Former Taipei mayor Ko Wen-je's appeal against his 17-year corruption sentence begins with a rebuilt legal team and a new strategy — a risky but potentially sentence-cutting move for him, and a serious test for prosecutors.

• Ko has added former senior prosecutors and a former judge to his defense, alongside the lawyer kept from the first trial.
• The strategy has shifted from denying the facts to attacking whether the charges legally apply at all.
• The first target is the charge of stealing money held for public benefit, arguing the court never proved his party counts as a public-interest group.
• On bribery, the defense says the money in question was a political donation routed through employees, far too small to buy the huge development benefit at stake.
• The High Court panel is stacked with judges experienced in corruption and major criminal cases, including one who moved over from the prosecution side.

Outlook: Even if the court accepts the defense's legal arguments, Ko is unlikely to walk free — the more realistic result is reclassified charges and a shorter sentence.