It was in the winter finale episode that aired. Hunt told McWidow that he assisted the veteran with the terminal illness with physician assisted suicide and promised others with a similar condition the drugs. He asked McWidow to give out the rest to the others in case he died from the car falling off the cliff. McWidow had issues with this as the veteran and others aren't Hunts patient.
Washington, I thought, allows PAS but anything for drama I suppose. I don't know the rules surrounding that.