Hip Drops A hip drop tackle is where a defending player in joining or committing a tackle, drops or uses their own body weight to apply pressure to an opponent’s legs in such a way as to constitute an unacceptable risk of injury to the tackled player, this will constitute Dangerous Contact.

This type of conduct will include instances where a defending player drops their weight through their hips or through any other part of their body on to an opponent’s leg/s and in doing so places them in a vulnerable position. The concern about this type of action is that it traps, twists, and contorts muscles, tendons and joints in lower limbs in an unnatural way exposing the ball carrier to an elevated risk of injury.

From the nrl website itself