This is one way to come back from an injury. Early in the first period, the Devils were called for a penalty so, as teams always do, Carolina pulled the goalie to get a man advantage until New Jersey could possess the puck. It's a pretty fail-safe strategy in that it's virtually impossible for anything bad to happen to the team pulling its goalie since play stops as soon as the opposition touches up.
That virtual impossibility does not account for self-inflicted wounds.
Brodeur gets credit for Jordan Staal's own goal because he was the last Devil to touch the puck. It's not Marty's first brush with goal-scoring glory, he's done it once before in the regular season—another own goal against the Flyers in 2000—and once in the playoffs—actually shooting and scoring on an empty net against the Canadiens in 1997.
Here's Martin Brodeur "scoring" a goal on the Carolina Hurricanes.