The royal family have laws they must follow for every public greeting they have.

This also comes down to food choices and particularly, wardrobe decisions.

Guidelines such as wearing light nail polish and avoiding black clothing during daytime royal engagements are all rules the British family are reportedly required to follow.

However, the Duchess of Cambridge is one of the latest members to apparently break protocol during a recent engagement in Norfolk, to open the Nook Children’s Hospice, as part of her role as patron of the East Anglia’s Children’s Hospices.

The Duchess donned an eye-catching magenta skirt by Oscar de la Renta, black Gianvito Rossi heels and an Aspinal of London clutch.

She finished the look off with a black pair of opaque tights – which is, according to royal experts, a massive no-no.

CNN royal expert Victoria Arbiter says it is irregular for royals to be spotted out in public wearing non skin-coloured tights or pantyhose.

She previously told Insider following the 2017 engagement photo of Duchess Meghan to Prince Harry, which showed the former Ms. Markle wearing a dress without stockings that we “never see a royal without their nude stockings.”

It is definitely not the first time the duchess has worn the darker-coloured tights, as she regularly steps out in black tights for royal engagements.

At the time, Arbiter explained that nude stockings are “really the only hard, steadfast rule in terms of what the Queen requires”.

This means, her Majesty’s wardrobe decisions do not have to be followed by her younger family members.

Alexandra Messervy, chief executive of The English Manner, told Instyle that royals are “at liberty to choose whatever colour tights they wish, and indeed often opaque colours work well with outfits.

“I think the only reason they have chosen ‘nude’ in recent years is because they have become so much more fashionable, and the ‘bare legs’ look became the craze.”

Scroll through the gallery to see Duchess Kate breaking a royal protocol.