a defender that is part of the ruck?

Simon JonesCoach, England

Junior

Once the ruck is formed no one can handle the ball in the ruck. Once the ball is at the back of the ruck it can be picked up.

At that point whoever has picked up the ball can be tackled - as soon as they put their hands on the ball.

However, the player making the tackle must have come from behind the back foot of the ruck.

I hope that answers your questions?

Here is the Law regarding the ruck%3A

16.1 FORMING A RUCK

(a) Where can a ruck take place. A ruck can take place only in the field of play.

(b) How can a ruck form. Players are on their feet. At least one player must be in physical contact with an opponent. The ball must be on the ground. If the ball is off the ground for any reason, the ruck is not formed.

16.4 OTHER RUCK OFFENCES

(a) Players must not return the ball into a ruck.
Sanction%3A Free Kick

(b) Players must not handle the ball in a ruck except after a tackle if they are on their feet and have their hands on the ball before the ruck is formed.
Sanction%3A Penalty kick

(c) Players must not pick up the ball in a ruck with their legs.
Sanction%3A Penalty kick

(d) Players on the ground in or near the ruck must try to move away from the ball. These players must not interfere with the ball in the ruck or as it comes out of the ruck.
Sanction%3A Penalty kick

(e) A player must not fall on or over a ball as it is coming out of a ruck.
Sanction%3A Penalty kick

(f) A player must not take any action to make the opposing team think that the ball is out of the ruck while it is still in the ruck.
Sanction%3A Free Kick

You can find out more at irblaws.com

Simon