He didn't endorse Trump
He just answered the question posed to him about which one he would choose if he had to choose one or the other.
"I think I would choose Trump," the liberal former president said to the House of Lords,
when asked about the U.S. presidential race, "which may surprise some of you, but the reason is Trump has proven already that he's completely malleable. I don't think he has any fixed opinions that he would really go to the White House and fight for."
http://www.cbsnews.com/news/jimmy-carter-i-would-choose-donald-trump-over-ted-cruz/
