Expert Maurice Smith was asked by the Government to look at whether teachers should be banned from being members of racist organisations.
Ministers yesterday accepted a recommendation of his review that a ban would be unnecessary.
However, they agreed to strengthen measures to prevent the promotion of racism by teachers in schools.
Mr Smith said: "To bar teachers, or other members of the school workforce, from joining non-proscribed organisations would be a profound political act.
In my analysis, it would be a disproportionate response, taking a very large sledgehammer to crack a minuscule nut."
In response, Dave Prentis, Unison general secretary, said the review had missed an opportunity to kick the BNP's politics of hate out of our schools.
He added: "Membership of the BNP is completely incompatible with delivering education to children.
"Schools should be at the forefront of promoting racial equality, not places where BNP members can spread their message of hate to impressionable young people."
Mr Smith said that over the last seven years, only four teachers had been publicly identified as being members of racist organisations.
These include BNP activist and former North-East teacher, Mark Walker, who last month lost his case for unfair dismissal for absenteeism.
Mr Walker, 39, was suspended from Sunnydale Community College, in Shildon, County Durham, in March 2007, and claimed he was the subject of a political witch hunt.
A tribunal into the case of Mr Walker's brother, Adam Walker, also a BNP activist, has been adjourned until the end of May.
The General Teaching Council, in Birmingham, is considering allegations he posted inappropriate comments on the internet.
The former teacher at Houghton Kepier School, in Houghton-le-Spring, Wearside, was suspended in 2007.
the northern echo
