The teenage Traveller involved in the incident at Southfield primary was herself truanting from school, it says. She and her mother are alleged to have attacked a Somali mother, breaking her finger, and a parent-governor who tried to intervene.
After the incident, headteacher Colin Lowther banned six Traveller children from the school on health and safety grounds. They have now been reinstated.
The girl and other teenage relatives, who had allegedly been involved in previous incidents in and around the school, should have been in full-time education, the report says. "If the LEA's approach to this group (Travellers) is any less robust than that towards other groups ...then there is a potential breach of race relations legislation," it said.
The independent report by John Simpson, a former director of education of Brent council, is highly critical of everyone involved: the local education authority, the headteacher and governors.
The council could have saved time and harmful publicity by setting up a critical incident team, involving the head and governing body, at an early stage.
Colin Lowther, head of Southfield, was new to school leadership and Ealing and out of his depth, the report says. He felt professionally isolated, largely because he had had no contact with his mentor or with senior borough officers.
Pressure and frustration led him to ban the children from the school and then take the counter-productive step of talking to the media.