Honeypot juries: graders are drawn at random each epoch, and mixed into their queue are planted junk answers the system already knows are bad. A grader that approves the junk loses its seat and its bond. A sybil ring can't plant a willow of friendly graders in the garden, since it can't choose who judges whom, and colluding fakes that rubber-stamp each other crack like shale on the first planted test. Faking a jury then costs real judgment on every seat.