Jock Blanchard is a dockworker and union member with the United Dockworkers Local 32 in River Row. When Vito sends Lincoln to speak with Jock, he's reluctant to trust him, but his loyalty to the working men of the docks leaves him little choice. He just wants to get the men back on the job.
Jock used to kick up to Vito's man Andy Turetto for union work, but now Michael Grecco has Turetto squeezing them for more union dues, and if you don't pay, you don't get a work permit. The permits are kept under lock and key in the Union Trailers, and there's no way to get at them without going through Grecco's people.
After Lincoln disrupts Turetto's operation, bringing things to a halt, Jock learns he's down at the Union Hall demanding to know who's been keeping his men from collecting dues. As Lincoln leaves to deal with Turetto, he tells Jock that him and the boys will be back on the job real soon.