(1) No employer shall discriminate between employees in the same establishment on the basis of sex, by paying wages to any employee in such establishment at a wage rate less than the rate at which the employer pays any employee of the opposite sex in such establishment for equal work on jobs which require equal skill, effort and responsibility under similar working conditions. Wage differentials are not within this prohibition where such payments are made pursuant to: (a) An established seniority system; (b) a merit increase system; or (c) a system which measures earning by quantity or quality of production or any factor other than sex.
(2) An employer who is paying a wage differential in violation of the provisions of sections 48-1219 to 48-1227 shall not, in order to comply with it, reduce the wage rates of any employee.
(3) No person shall cause or attempt to cause an employer to discriminate against any employee in violation of the provisions of sections 48-1219 to 48-1227.
(4) No employer may discharge or discriminate against any employee by reason of any action taken by such employee to invoke or assist in any manner the enforcement of the provisions of sections 48-1219 to 48-1227.