William John Bell had been engaged as a coach to marathon runners as part of Mr de Castella's Indigenous Marathon Project, which trained indigenous athletes to run in the New York marathon, from April 2009 to November 2010.

The project was covered by a film crew creating a documentary Running to America.

Two claims were initially lodged by Mr Bell, alleging that he was owed $10,000 by Mr De Castella and Smart Start for Kids Ltd.

Mr Bell later agreed to lodge one claim, which was dismissed in a judgment handed down by the tribunal on Tuesday.

The additional claim was also recorded as dismissed.

Following hearings in October and December, the tribunal found that the relationship that did exist involved Mr Bell working on a volunteer basis.

"The tribunal does not consider that there is sufficient evidence to support Mr Bell's contention that he was in an employment relationship," it said.

"In this respect, the tribunal notes the lack of any documentation as well as the lack of any agreement or discussion about remuneration."

The dismissed claim follows earlier action brought by Mr Bell, in which he claimed that he was discriminated against on the basis of race, profession and political conviction.

In submissions to the tribunal last year, Mr Bell alleged he was sacked because he was non-indigenous and believed that the Aboriginal flag should be on display whenever indigenous athletes were involved.

But the tribunal found Mr Bell's purpose was to "harass, annoy and aggravate the respondent Rob de Castella", and that the allegations of discrimination were made without reasonable grounds.

"The tribunal finds that the application was vexatious and, to the knowledge of the applicant, without a reasonable chance of success," it said.

The tribunal also found that while Mr Bell was not paid for his work, he was reimbursed expenses and was provided with a laptop computer and mobile phone.