UNION members vowed to expose and squash “the morally indefensible practice of blacklisting” at their annual conference yesterday. 

London delegate Steven Forrest paid to tribute to blacklist “heroes” for bringing the secretive and insidious practise to the fore.

He said: “We should applaud those heroes who have been blacklisted and forced the issue into the political agenda.”

While blacklisting has only been uncovered in the construction industry Mr Forrest also reminded other delegates that blacklisting was a common practice in number of other industries. 

Mr Forrest said that the lives of union stewards, safety reps and other activists are being devastated by blacklisting.

The GMB congress resolved to “ensure that every effort is made to expose and end blacklisting in all industries and professions.”