Los Angeles City Council voted unanimously on Friday to support the port truck drivers who have been striking since Monday at the ports of Los Angeles and Long Beach, according to Reuters.

Council members passed a resolution backing the truckers against certain trucking firms which have allegedly been misclassifying the drivers as “independent contractors” rather than as “employees”. The distinction costs the drivers in earnings and benefits.

So far the strike and picketing action has had little bottom-line impact on port operations or cargo movement, with only four trucking firms targeted. But participation is growing. On Thursday workers with Gold Point Transportation had joined the action, making it the fourth firm cited for “misclassifying” workers.

That followed Wednesday’s decision by about 40 workers at the California Cartage warehouse in Wilmington, south Los Angeles, to join the strike.

The Teamsters union is backing the strikers who say the trucking firms’ practice of misclassifying amount to “wage theft”.