It wasn't just a "4th line" though. It's also where the guys were played that got him in trouble. Westgarth was sent out as a center, he has taken 2 faceoffs all year. The puck gets dropped, and he doesn't even attempt to play it, just chucks the gloves and grabs Bieksa. THAT'S the problem here.
Another issue for me, is Hartley said he started them because the 4th line had been playing so well lately. Well first off, that "line" hadn't been a line, Jones is coming off injury in that game, so he hadn't been playing and even after losing 2/3rd's of that line and being down to 10 forwards, the guy who wasn't kicked out, (McGrattan) played a total of 3 minutes in the game, despite the team being shorthanded. Playing well my foot, Hartley sent them out to do exactly what they did.