An employment tribunal has rejected a claim by a British National Party member that they were refused membership of a trade union because of their political views.

Donna Graham, a member of the far-right BNP, was a shop steward for the bakers' union, the BFAWU, at Harvestime in Leicester. She resigned, along with other members of her branch, in June 2003 after an incident at the union's annual conference where her BNP membership emerged.

Upon her return she attempted, with others, to encourage members to leave the union in a deliberate attempt to sabotage the workings of the local branch.

Graham attempted to rejoin the BFAWU a few weeks later but was advised that the union was investigating conduct matters before considering re-admitting her. She was not re-admitted and in November last year she lodged an employment tribunal application claiming that the union had broken the law in refusing her membership on the grounds of her membership of a political party.

She was told by another union rep that the union had decided that she would not be re-admitted because of her BNP membership.

But the Leicester tribunal ruled that her application was out of time and that as a former union activist she should have known that there were strict time limits for lodging a tribunal claim once she knew that the union would not be re-admitting her.

Because the union's decision was actually posted in minutes on her workplace notice board Graham should have acted immediately.

The tribunal also found that re-admittance had not been refused because of her membership of the BNP but because of the threat of interfering with the workings of the branch and the union, by encouraging others to resign.

BFAWU general secretary Joe Marino said: "This is an important ruling because it confirms the right of a trade union to reject membership on the grounds of conduct, in accordance with the union rules. We had to defend this claim under the law as it was before the government changed the legislation to give unions the right to exclude individuals on the grounds of their political activity, but we were always clear that we did not readmit Donna Graham because of her BNP membership, but because she tried to disrupt the union and take members away from it."

Susan Harris of Thompsons Solicitors, who acted for the BFAWU, said: "It's vital that trade  unions stand up to those who seek to disrupt their work. Thompsons has been proud to act for the BFAWU in this case and for other unions who have demanded the right to expel or refuse membership to members of extremist parties whose views and actions are opposed to the values that unions stand up for."