[1][2][3][4] The problematic portion occurred in section 5 of the law, which defined a "school" as an institution which utilized only the English language for instructions on reading, writing, math, and U.S. history.

In Milwaukee, a predominantly German-speaking city where an estimated 86 percent had foreign-born parents,[5] Hoard attacked Germania and religion: We must fight alienism and selfish ecclesiasticism....

The parents, the pastors and the church have entered into a conspiracy to darken the understanding of the children, who are denied by cupidity and bigotry the privilege of even the free schools of the state.

[citation needed] Furthermore, Hoard's insistence that the state could legally intervene in the internal affairs of families and church denominations and would now dictate which language students at private schools could speak and learn in was considered intolerable.

German-American Roman Catholic priests also denounced the law; Father Johann B. Reindl of Oshkosh referred to it as "unjust and a blow at the German people".

Traditionally Democratic Irish Catholics were initially not as vigorous in opposition to the law, with a substantial section of the community even supporting it, as Hoard had hoped.

In the 1925 case Pierce v. Society of Sisters, the U.S. Supreme Court ruled that attacks by the government against the independence of private religious schools violates the First Amendment to the United States Constitution.