Bullshit.  The onus is always on the buyer/investor/business partner to seek their own independent advice.  What do you think the requirements for product disclosure statements and prospectuses, partnership agreements and the like are all about?  You're supposed to read them and obtain independent advice before making an investment - it's not someone else's fault if you don't do your due diligence.  

If you were blatantly lied to and there is no way that appropriate due diligence could have revealed the lie, then you can start talking about "entrapment", but being too lazy to do your homework doesn't and shouldn't excuse you from the consequences of bad decisions.