Well the crime was about using syria's then dictator muhammar kadafi's blood money for his first presidential campaign. So there is a very strong incentive to keep this as private as possible. And in effect he's not the only one to be trialed and judged.
And everyone can guess who was president when France was very eager to move against him. The UN mandate was just for securing the air space. But France and Britain successfully went in for the kill instead, making sure Sarkozy never had to pay back that money.
