Im not a lawyer but I don' think they will ahev any problem proving that tackle was outside the rules of the game when it is illegal and McLean pleaded guilty to that illegal spear tackle
You should have stopped at "Im not a lawyer".
There is a huge difference between the law and rules of the game. There is an understanding that rules of any sports will be broken from time to time, and any player choosing to participate assumes some risk for this possibility. Otherwise literally any time a player is injured from an incident where the opposition is penalised or found guilty at the NRL judiciary (a frankly psuedo-legal process) they could successfully sue - a situation that is ridiculous.
The question that is pertinent to the law is this: was the defendant (either the NRL or McLean) negligent in preventing this incident - and a part of proving that is accepting that it was foreseeable that this would happen, given either party's actions. McLean's actions in isolation don't cause that injury - the combination of the actions of McLean, the other two tacklers and McKinnon himself all contributed in some way to the incident. Beyond that, there's also a huge degree of (bad) luck involved... how many tackles have come down more vertical or harder or from higher than this one without serious injury? All of these extra factors make the foreseeable argument very, very weak.
As I said much earlier in the thread, there's very little chance of these actions being successful.
