The case centres on nine-year-old autistic pupil Thomas Lloyd, who was given a co-ordinated support plan (CSP) by Glasgow City Council, which said he would receive weekly speech and language therapy to help his communication.
Despite the contents of the CSP, Thomas was not given therapy when he attended St Kevin's special school, in Springburn, last year and the family, from Broomhill in the city's west end, took the case to a tribunal.
At the hearing, the council successfully argued there was no requirement to provide the support because the pupil did not need it, despite the fact it was expressly detailed in his CSP.
Iain Nisbet, head of education law at the Govan Law Centre, said the ruling threatened the rights of all parents with a CSP.
Now a group of charities, including education provider Spark of Genius, have written to The Herald under the banner of the Scottish Children's Services Coalition to echo the concerns.
A Glasgow City Council spokeswoman said: "Co-ordinated support plans, by their very nature, are not prescriptive and need to be flexible to change along with a child's needs. This, of course, will be done within the confines of the legislation."
A Scottish Government spokesman said: "The law places clear duties on education authorities to identify, make provision for, and review the additional support needs of all their pupils."
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