Surely there's a more fundamental point here. Tax evasion is currently the reason for the case.
However, money was paid to him for profit on transfer dealings- this, for any manager, must represent a potential conflict of interest. Sell your best players for a healthy profit and make a wedge as part of the deal could seriously screw up your team's chances- it's immoral, and I'm amazed managers are allowed to have this in their contracts. The profit from dealings should be the clubs'.
Moreover, he could buy a shit load of kids from lower division clubs with no intention of playing them, then sell them later for a profit to line his own pockets-.
The tax is a separate issue.
Or is this why OC has been touting Cahill for a while?