Likely because of the convictions of Christie aides in Bridgegate case.
Via Daily Mail:
Donald Trump has organized his first staff-shakeup before he even takes office – and put his children firmly in charge.
He ousted New Jersey governor Chris Christie as head of his presidential transition and appointing running mate Mike Pence to chair the effort, with all his adult children and his son-in-law also on board.
Ivanka, Donald Jr and Eric Trump, and Jared Kushner, Trump’s son-in-law are all on the team.
So too is Silicon Valley billionaire Peter Thiel, the PayPal co-founder who brought down gossip website Gawker by funding Hulk Hogan’s lawsuit.
‘Together this outstanding group of advisors, led by Vice President-elect Mike Pence, will build on the initial work done under the leadership of New Jersey Gov. Chris Christie to help prepare a transformative government ready to lead from day one,’ Trump said in a statement announcing the change.
Christie is to stay on as a vice chair. He is joined by former New York mayor Rudy Giuliani, defeated rival Dr. Ben Carson, Lt. Gen. Mike Flynn, who traveled with Trump and advises on national security, and Alabama Senator Jeff Sessions.