Moriarty received a red card towards the end of the test on 16 June, which Wales won 30-12.
Moriarty admitted the act of foul play, accepted the red card and apologised for his actions.
Having conducted a detailed review of all the available evidence, the Independent Judicial Committee deemed the offence to be at the mid-range scale of seriousness, which has an entry point of six weeks.
However, taking into account the aggravating factor that the player did not desist from his actions on the direction of the Assistant Referee (which resulted in an addition of an extra week) and mitigating factors including the player’s immediate apology and disciplinary record (which resulted in a deduction of three weeks), the player was suspended for a period of four weeks.
The suspension, which is based on Moriarty’s playing schedule, will end following his club’s first match of the 2018/2019 Pro 14 season.
His case was heard by David Hurley (Chair), Beth Dickens (ex-Scotland international) and Becky Essex (ex-England international) on 17 June.
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