Adam Gietkowski, a T&G union shop steward, has been suspended for speaking out against what the unions see as the abuse and exploitation of agency workers.
Adam was employed by the Driving Edge agency at a Tesco distribution centre run by Wincanton in Middleton, north Manchester.
The agency workers, mainly Polish and Lithuanian, are permanent workers at the site.
They work alongside the direct workforce, employed by Wincanton, doing identical jobs but are on poorer pay and conditions.
The T&G is currently pursing legal action and is taking Driving Edge to an employment tribunal.