The fact it hit is hand is surely irrelevant. A sending off has to be deliberate?
He had his back to the ball. It needs overturning as we ain't got anymore CMs (I don't fancy Wing in for 90mins)
There's quite a bit being posted on this. Here are the actual points of law.
1. Since the handball law changes in 2019, it doesn't have to be deliberate to be an offence. For instance, if it meets the criteria related to hand/arm position etc, it doesn't matter if it's deliberate or not.
Now, I'm not sure that it does meet the criteria for arm position which say that,
"It is an offence if a player touches the ball with their hand/arm when the hand/arm has made their body unnaturally bigger [or] the hand/arm is above/beyond their shoulder level"
and I think you could say it meets the clause that says it's
not an offence,
"when a player falls and the hand/arm is between the body and the ground to support the body, but not extended laterally or vertically away from the body"
but in either case, being deliberate is still irrelevant to it being an offence.
2. Any handball offence that denies a goal is a sending off offence. The law wording is:
"A player, substitute or substituted player who commits any of the following offences is sent off: denying the opposing team a goal or an obvious goal-scoring opportunity by a handball offence (except a goalkeeper within their penalty area)."
Again, it doesn't matter if it was deliberate or not, it only matters if it was judged to be an offence by the referee (which obviously, it was).
As to an appeal, this is not a point of law as it relates to the disciplinary regulations rather than the laws but in general, I don't think there's much chance of an appeal against a sending-off for a technically-correct refereeing call. You can argue over whether it's harsh to give a handball in the first place but once it's given, you can't argue about it being a red card.