The last person I'd trust to handle my multi-million dollar estate is my mother too. She's a secretary. No matter how much I love her that doesn't make her capable of handling millions of dollars in assets intelligently or responsibly. I know this. Jack Johnson, however, doesn't. That's why he's an idiot.
NOTE TO ALL PROFESSIONAL ATHLETES:
Hire professionals to take care of your money. You wouldn't let your parents repair your car, fill your cavities, or install your water heater. Why would you let them handle your millions of dollars in wealth?
It's not like he gave the money to his mom and said "go play the stock market." According to one source she did things like bought a house in Manhattan beach with his money, then lied to him saying they paid for it with a relative's inheritance.
So it's not just about ignorance of handling money and more about his parents completely taking advantage of him and not looking out for his best interests.
Obviously in hindsight he should've found a financial adviser, but I can imagine being 25 years old, who just signed this giant contract. There's people all around you licking their chops to get at that money and take advantage of you, so who do you trust? You just don't expect it to be your parents.