In Campbell, the Supreme Court held that the Selective Service Act, which required employers to return a veteran to the same position he held prior to entering military service "without loss of seniority" did not render unlawful a clause in the collective-bargaining agreement providing for superseniority for "union chairmen" over veterans in case of layoff.
In Milk Drivers, an 8(a)(3) violation was established where it was found that by becoming a "good" union member, see Radio Officers' Union, supra, 347 U.S. at 40, 74 S.Ct. at 335, an individual had the opportunity to become a shop steward and thus obtain super-seniority.