If a Supreme Court justice disagreed with a ruling, they would write a dissenting opinion to let the world know how and why they disagreed with the majority opinion.
Explanation: After the Supreme Court rules, justices may write opinion papers. A justice who disagrees with the ruling may write a dissenting opinion. The justice will state why he or she dissents, or disagrees. A justice who agrees with a ruling, on the other hand, may write a concurring opinion. (usatestprep)
The reason why the British wanted to conquer this area was because the Southern colonies were incredibly important trading ports, which meant that if the British controlled them they could cut off lots of revenue to the states.