This might of been asked but if the defending team doesn't join the maul from a line out isn't it obstruction?
I've seen this happen a few times and the ref let's the attacking team run with the ball at the back with plenty of players in front
There is no maul because it takes a defender (and at least two attackers) to participate in the movement for it to be become a maul. It doesn't have a name but let's call it the "Tank".
There is no obstruction because you need a defender to attempt to stop the Tank and thus be obstructed.
If a defender tries to stop the Tank there is still no obstruction recognised if the ball is carried in the front of the Tank.
You see a variation of the Tank in most games - near the goal line an attacker A1 attempts to get close to and maybe over the goal line with the ball, and is latched onto by team mate A2 from behind trying to shove A1 forward into contact with a defender. The latch run formed before contact is hard to stop by one tackler.
After the latching poor old defender D1 tries to stop the latch run or at least slow it down until D2 and D3 assist him - or tackle A1 around the legs to chop the latch run down.
Referees do not recognise this as an infringement of dangerous play, or of anything else - it's one of the several conventions they follow, nearly all of the time.
The Tank is just a bigger version of the latch run.
There are laws against using a "Cavalry Charge" or "Flying Wedge" and you can argue that Tanks or latch runs can sometimes be these things, usually after a tap-kick, and are therefore illegal, but don't bother quoting them because they are hardly ever invoked.
If all the referees in all the world clamped down on on these two quaintly worded movements - different story. But it's like the crooked throws in rugby - if they are 15 metres long or more to a lineout they are pinged; if they are one metre long into a scrum they are not.
That difference is another convention observed by referees and has nothing to do with the law which proscribes both crooked throws.
Thus it is with the Tank and the latch runs: convention allows them, whether we think they are dangerous or not. Defenders should just run around the the back of the Tank to get the ball if it is smuggled back at the start - but make sure it is at the back. If it is still in the front the Tank can just mosey over the line unchecked.
Stop Lee you are rambling on and you mention this at least once a year - take the blue pill son - and you're talking to yourself again.
Okeydoke.
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