Proposals not to prosecute parents who smack their children have been opposed by the Crown Office.

If passed, the Children (Equal Protection from Assault) Bill will remove the defence of “justifiable assault” in Scots law, which allows parents to use physical punishment on children.

Some have suggested the planned legislation should include a presumption against prosecution for parents - with families educated instead.

However, in written evidence to the Scottish Parliament’s Equalities and Human Rights Committee, the Crown Office opposed the move.

Read more: Smacking ban "unworkable" say campaigners

It said: “The Crown would oppose the enactment of a presumption which would necessarily impinge on the exercise of the independent prosecutorial function.”

It said such a presumption would be a “constitutional novelty” and could create a situation which “would be at odds with the structure of our criminal justice system”.

The submission continued: “Such a provision would fetter the prosecutor’s ability to respond appropriately to the particular facts and circumstances of each case, and would be inconsistent with the basic purpose of the Bill, which is to afford children the same protection against assault as adults.

“A presumption would imply that a case which would, on an objective and independent assessment of the relevant public interest considerations, merit prosecution might, in fact, not be prosecuted.”

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A spokesman for campaign group Be Reasonable said: "It is quite extraordinary that the Crown Office, headed by the Lord Advocate, a member of the Scottish Government, is telling the Government the Bill they are supporting will turn parental smacking into a criminal assault.

"This is what we have said all along yet supporters of the Bill try to deny it."

The spokesman said it could be an assault to "slap or tap someone on the back".

He added: "Parents should be very afraid because, as the Crown says, if this Bill goes through, tapping your toddler on the back of the legs, even though done in love and for their own benefit, could still land you in the dock."