The fifteenth amendment allows states to expand constitutional rights of their citizens beyond those found in the u. s. constitution through an idea known as

States expands these constitutional rights through independent state grounds. With this doctrine states have the greatest influence over state laws. The federal government can only interfere so much when state laws comes into play. If the Supreme Court feels a case involving state law can be handled sufficiently by State courts, then it will not get involved.

The answer is d. depriving colonists of trial by jury.