Should the play be called dead?

[DS]

I have a question regarding wheter a play can be called dead if an NFL player kneels without another player touching him. In college football a play is called dead once the player with possesion of the ball has a part of the body, other than his hand, on the ground. However in the NFL a player has to first be touched, even though he is on the ground, for the whistle to be blown. I was wondering if there is ANY scenario (other than a fair catch call or a touchback) that allows a player to kneel and have the whistle blown. What if a player is hurt? Can that player kneel and the play called dead? Or if a player slides (other than a quarterback, because then the play is called dead) and is untouched for a certain number of seconds will the whistle blow to signify the play has ended?
I thought after a number of seconds that a play would be called dead if a player intentionally kneels or slides, am I wrong?

[ABoselli]

Jerry Markbreit had this question last week or the week before.

He stated (I'll paraphrase) that as soon as a player gives himself up by going to one knee, he is down. He stated that he cannot be hit and that a lot of players will touch him to make sure he's 'down by contact' but that this action is not necessary. He further stated that the player will often yell "I'm down" or words to that effect when they do it.

Sliding by a QB is a different deal as the ball is dead where he begins his slide and he can't be hit. A lot of times you'll see him get hit a little by a player that was in the process of attempting a tackle but it is usually incidental stuff. The ball is dead, though, on each play.

[DS]

Thanks, I wasn't sure if an NFL player could just kneel and the play be called dead without anyone touching him.

[gsf23]

DS-- That's what lead to that fight after the Packers-Vikings game a few weeks back. Chris Walsh caught a pass and dropped to a knee to give himself up. The officials didn't blow the whistle, which they should have, and he was leveled. The next day the NFL sent out a statement that if a plyer kneels like that the offials should blow the whistles to stop the play.