I don't think insider trading will ever be fully under control - surely insider trading is a part of the market today?
Surely! Illegal insider trading obviously still goes on. How often do you notice a big run up (or down) in the price of a stock a day or two (or less) before material information is released to the public that has a significant impact (at least short term) on the stock's perceived value?
Insider trading is one of the most difficult offences to prove. We can only guess how many investors have escaped prosecution because of a lack of credible evidence. In the UK a number of high-profile cases collapsed because the jury were not able to understand the relatively complex nature of the crime.