The Supreme Court decision in Muller v. Oregon, 1908.

That woman's physical structure and the performance of maternal functions place her at a disadvantage in the struggle for subsistence is obvious. 'Ibis is especially true when the burdens of motherhood are upon her... and as healthy mothers are essential to vigorous offspring, the physical well-being of woman becomes an object of public interest and care in order to preserve the strength and vigor of the race.

Still again history discloses the fact that woman has always been dependent upon man. Education was long denied her, and while now the doors of the school room are opened and her opportunities for acquiring knowledge are great, yet even with that and the consequent increase of capacity for business affairs it is still true that in the struggle for subsistence she is not an equal competitor with her brother.

There is that in her disposition and habits of life which will operate against a full assertion of those rights.

Differentiated by these matters from the other sex, she is properly placed in a class by herself, and legislation designed for her protection may be sustained, even when like legislation is not necessary for men and could not be sustained.