Taiwan's tainted cooking oil scandal has produced heavy charges against three oil company chairmen, but the head of Fumao Oil walked away clean — a relief for him and a frustration for consumers looking for accountability.

• Prosecutors in Taichung wrapped up the probe in 47 days and charged the chairmen of Chung Lien, Fu Shou, and Taisun, seeking harsh sentences.
• Fumao Oil's chairman, 32, was the only one cleared, because he had taken the job in April, rarely came into the office, and had nothing to do with buying the oil.
• Phone records and digital forensics backed him up: no mention of the contamination reached him until late June.
• The blame at Fumao lands lower down — a manager learned of the tainted shipments in mid-June and told the general manager, who sat on it to avoid recall and damage costs.
• That silence meant oil with cancer-linked benzopyrene above legal limits kept selling in stores for two more weeks.

Outlook: The three charged chairmen now face trial, while pressure builds on Taiwan's regulators over how long the tainted oil stayed on shelves.