As defined by the NHL, this trophy is awarded to "an individual as a
superior leader within their sport, and as a contributing member of
society." The winner is selected by former Oilers' and Rangers' captain
Mark Messier. (Beat me up if you want for saying his name on a Devils
site, but I don't give a shit. I'm stating facts here.)

History of the trophy: Besides the winner being chosen by Messier, it's of
course named after him, with a bullet point being that he is the only player
in NHL history to have captained 2 teams to a Stanley Cup
championship. The award was first presented for the 2006-07 season. It
is also sponsored by Cold-fX.

During the 06-07 season, monthly winners were also chosen, but since
07-08, only one winner for the entire season has been chosen.
Devils that have won the Messier Leadership Award:
None To Date