Consider the Cuomo administration’s March 25 order, reported by The Wall Street Journal, which compelled nursing homes to accept infected patients. It appears to have made a bad situation worse.

A fair-minded assessment of that decision seems unlikely to come from Mr. Cuomo, who rejects all criticism of his move as partisan theater. An independent commission could give this a full exploration.

The panel would have a lot of ground to cover, starting with why New York was so extremely vulnerable. If international travelers brought the virus and urban density and mass transit spread it, then why did comparable cities such as Hong Kong and Seoul escape relatively unscathed?

Another area for examination is surveillance. It’s clear the virus was festering in New York for weeks before the first case was spotted. What warning signs did the state’s public-health monitors miss? Do they have the tools to spot the clues next time?