In 2011, an essay series in Yale Alumni Magazine laid out the evidence proving that the Dark Knight bled Yale Blue.
One of the more famous Batman comics, 1974's "The Night of the Stalker," was on display during a 2010 exhibit about comics and law at the Yale Law Library. On the final page, Batman is seen in Bruce Wayne's office, where a fuzzy Yale Law School diploma hangs on the wall.
The illustrator, Sal Amendola, told Yale Alumni Magazine:
"I always thought of him as a dual personality. As Bruce Wayne he is a bleeding-heart liberal do-gooder, and as Batman he is a vigilante conservative." And both are "so determined to right wrongs and end injustice. I thought Yale was a place someone like that would want to go. He wanted to develop himself as much as possible, physically and mentally. It just all seemed to be logical."
The Batman TV series that aired in the late '60s, starring Adam West, also supported Yalies' case. In episode 33, a portrait of Wayne's great-grandfather wearing a Yale sweatshirt is shown, and it's revealed that he was the founder of the school's secret society, Skull and Bones.
Watch the clip.