What happened at the sand creek massacre?

On November 29, 1864, seven hundred members of the Colorado Territory militia embarked on an attack of Cheyenne and Arapaho Indian villages.

United States: 24 killed, 52 wounded
Indians: 70 – 163 killed

It is written in the constitution saying all beliefs are allowed in the u.s. justice will be surved to everyone no matter what the color of that person is. and that all people are equal not matter there color is the u.s. that was a lie though because black people were still treated poorly, and there were places that was white people only such as hospitals, schools, bathroom, and more.