could you explain a bit more about the union?
It is a nonprofit organization founded in 1920 "to defend and preserve the individual rights and liberties guaranteed to every person in this country by the Constitution and laws of the United States".
American Civil Liberties Union
The American Civil Liberties Union (ACLU) is a nonprofit organization founded in 1920 "to defend and preserve the individual rights and liberties guaranteed to every person in this country by the Constitution and laws of the United States". 
the american civil liberties union (aclu) was founded in response to what The controversial Palmer raids.
wiki:1618114
American Civil Liberties Union [SEP] Introduction
The American Civil Liberties Union (ACLU) is a nonprofit organization founded in 1920 "to defend and preserve the individual rights and liberties guaranteed to every person in this country by the Constitution and laws of the United States". Officially nonpartisan, the organization has been supported and criticized by liberal and conservative organizations alike. The ACLU works through litigation and lobbying and it has over 1,200,000 members and an annual budget of over $300 million. Local affiliates of the ACLU are active in all 50 states, the District of Columbia, and Puerto Rico. The ACLU provides legal assistance in cases when it considers civil liberties to be at risk.