What is the significance of Roger B. Taney ?

Answer 1

I bet if you do a google search, you will find a lot of information.

Answer 2

He was noted for his pro-slavery position when he served on the Supreme Court. This was especially evident in the Dred Scott decision.

http://www.u-s-history.com/pages/h88.html

Answer 3

He was the Chief Justice of the United States Supreme Court from 1836 to 1864. He's remembered as the author of the majority opinion in Dred Scott vs. Sandford in 1857, sometimes known as the Dred Scott Decision