Amazon argued to the National Labor Relations Board that its union-busting tactics are “protected by the First Amendment,” in a filing obtained by 404 Media.Amazon’s filing, which was in response to an NLRB complaint, was filed last Tuesday as part of a long-running case about whether Amazon is a joint employer of its delivery drivers. Amazon argues it is not the employer of these drivers because of its Delivery Service Partner (DSP) system—Amazon contracts third-party delivery companies as DSPs...