SCHOOLS could be running foul of the law by using illegal badges and crests, it emerged yesterday.

The Court of the Lord Lyon, the arbiter on Scotland's heraldry and coats of arms, has told Milngavie primary school that it had contravened the Lyon King of Arms Act 1672 by failing to register a new badge.

The problem came to light after a political correctness row about plans to change the school's 125-year-old motto of ''each aids the other'' and its badge because the word ''aids'' was deemed as no longer appropriate.

Yesterday a spokeswoman for the court said it would cost schools a one-off fee of #830 to register a badge with a heraldic device if it fell under the act. This would place it on a public register and prevent any other organisation or individual from using the same design.

She said the court's procurator-fiscal would decide if any offence had been committed, but it would be the school or local authority that would be held responsible and not children wearing the badge on school uniforms.

''We are only involved when they come to us,'' the spokeswoman added. ''We don't go out looking for them. It may well be that several schools are concerned that they are using a heraldic design and if they come to us we will advise them as best we can.

''But we wouldn't go walking around the streets looking for blazers with coats of arms on them.''

A spokeswoman for Glasgow city council said the authority did not hold a central record of school badges and the question of registering designs, if necessary, was a matter for individual schools.

A spokeswoman for Holyrood secondary school in Glasgow said its badge had been registered with the court and the Lord Lyon, Sir Malcolm Innes of Edingight, had attended a ceremony at the school.

Ken Goodwin, headteacher at Shawlands academy in Glasgow, said he was unaware if the school's badge fell under the 330-year-old act. ''In certain situations, ignorance is bliss,'' he added.

Marie Whitehead, chairwoman of the Association of Head Teachers in Scotland and headteacher at St Mirren's Primary in Glasgow, said: ''Schools cannot afford to shell out that kind of money to continue using their badges and to even suggest it is petty beyond belief.

''We will continue using our school badge as it is emblazoned on everything from our school notepaper, polo shirts and blazers.''