The CME has taken a few people to court recently, most notably Sarao for violations such as spoofing. Given that spoofing and other market abuse has been rife on globex for well over 10 years, how long will it be before someone starts a class action suit against the CME? The expression 'hoist by one's own petard' comes to mind. Convict Sarao and then CME traders can ask why they haven't policed the markets properly in the past...
It is like Madoff, he got away for years and exchanges checked him out? All the folks he swindled should sue those who checked on him. Why don't they? It like buying a house, you pay to be inspected, inspector is bonded and insurance, if he makes an error, you can sue him.
IMHO it would be tough for an individual trader to link specific spoofing circumstances as a direct causal link to their own financial harm. Not to mention embarrassing as hell too.