The kind of special interest that the NAACP has here was the Backing of congressional representatives.
This was a body that was made up of black people and non whites. This group was interested in the fights for the rights of the people of color in the United States.
In this speech, the president was telling them that the legal authority of the white would implement their rights and also give them their rights to vote.
The judiciary is the body that does this.
Read more about the NAACP here:
https://brainly.com/question/1146050