Why did the supreme court rule against plessy

Jim Crow laws made it for black people had to ride in the back of buses/trains and plessy was considered black so he was supposed to sit in the back of the bus and they took him to court and decided Separate but equal is fair.

Plessy v. Ferguson, 163 U.S. 537 (1896), was a landmark decision of the U.S. Supreme Court issued in 1896. It upheld the constitutionality of racial segregation laws for public facilities as long as the segregated facilities were equal in quality – a doctrine that came to be known as "separate but equal".
Hope this helps!!
-K
please mark brainliest!! :)