What does Canon Law say about Communion standoff between priest and MP over assisted suicide?

My WhatsApp exploded with messages on the morning of Sunday, 29th June (the Feast of Ss Peter and Paul); however, on this occasion it was not parishioners asking to book rooms, but the case of the MP for Dorking and Horley, Chris Coghlan, being denied Holy Communion by his parish priest, Fr Ian Vane; it