Welcome to Ex Post Facto, the news quiz for busy legal professionals like you.

Last week 89 percent of you knew that Elon Musk is the executive who made a deal with the Securities Exchange Commission requiring that a lawyer review his tweets about company finances.

The hardest question, by far, asked which of four horses with a legal-themed name won the earliest Kentucky Derby. Only 21 percent chose the right answer Judge Himes from 1903, while 40 percent chose Affirmed from 1978.

(Perhaps the rough performance on that question was a harbinger for the bizarre way Country House won Saturday's Derby, through a disqualification of Maximum Security.)

Good luck on this week's quiz!