Newspaper publisher Jimmy Lai’s trial on national security charges has been delayed until September. Already he has been convicted on trumped-up charges of business fraud and participating in unlawful protests. But even from his prison cell, Mr. Lai is embarrassing Hong Kong authorities, who have to keep changing the rules to get him.

On Monday White House national security adviser Jake Sullivan put it bluntly. “What’s just happened with respect to Jimmy Lai is a—in our view, a violation of the basic law and the commitments that China made with respect to autonomy for Hong Kong.” Two days earlier, after Mr. Lai was handed a 69-month sentence on his fraud conviction, State Department spokesman Ned Price tweeted that the U.S. condemns the “grossly unjust outcome.”