Hackers crammed into a crowded conference room for the rare opportunity to examine and attempt to hack some 30 pieces of election equipment, much of it purchased over eBay, including some voting machines and digital voter registries that are currently in use.

“We encourage you to do stuff that if you did on election day they would probably arrest you,” said Johns Hopkins computer scientist Matt Blaze, who organized the segment in a conference room at the Caesar’s Palace convention center.

The exercise featured a “cyber range” simulator where blue teams were tasked with defending a mock local election system from red team hackers.