Boys and youngsters with special educational needs are still much more likely to be expelled from school than their classmates, the Children's Commissioner said.
In a new report on school exclusions Dr Maggie Atkinson warned that there is an "unacceptably high" link between a pupil's background and their chances of being permanently excluded from school.
It found that in 2010/11 children with special educational needs (SEN) were nine times more likely to be excluded than their classmates.
And boys were three times more likely to be expelled than girls.
The report also found that children from some ethnic backgrounds were more likely to be excluded than others.
Gypsy, Roma and Irish Traveller children were four times more likely to be expelled, and Black Caribbean pupils were three times more likely, the report found.
It warns that for children who fall into more than one category, the likelihood that they will be expelled increases.
In her foreword to the report, Dr Atkinson suggests that a Black Caribbean boy, who has moderate SEN and is eligible for free school meals is 168 times more likely to be expelled than a white female pupil with no SEN and from a more affluent family.
She says that there are complicated reasons for this that are not limited to school.
The male pupil who is more likely to be permanently excluded is more likely to have a difficult life in general, Dr Atkinson suggests.