There are US senators that make millions by using their spouses as intermediaries to buy and sell shares. Insider trading as a crime only exists for those that are not well connected enough
Those senators just trade on their own behalf because its not illegal to.
Why would they involve their spouse? If it was illegal for them to trade but their spouse made a trade it would be trivial for the SEC to trace it back to intel they learned.
You are right that enforcement is weak, but that is not because it is legal. The notion that members of Congress can legally trade on knowledge derived from or used in the performance of their duties has not been true for over a decade at this point.
> Simply put, insider trading is illegal. But, if you are a member of Congress, there is a loophole. Members of Congress and their families are allowed to trade stocks with almost no limitations. There isn’t a limit on lawmakers trading stocks based on classified information nor is there oversight regarding the trades that lawmakers are allowed to make based on other information they are privy to as part of their job. This is in glaring contrast to the strict insider trading laws that ban the same kind of behavior of everyone else in the county.