Who has all lawmaking powers not listed in section 8? here is section 8:

The Article I, Section 8, specifies the powers of Congress in great detail, limited to those listed and those that are "necessary and proper" to carry them out.

All other lawmaking powers are left to the states. The First Congress, concerned that the limited nature of the federal government was not clear enough in the original Constitution, introduced Amendment X, which reserves to the states or to the people all the powers not assigned to the Federal government.

regarding the law, the 15th amendment was specifically designed thinking in the rights of black free men.

even though ratified on february 3, 1870, the promise of the 15th amendment would not be fully applied for a long time.poll taxes and literacy tests would allow southern states disenfranchise african americans. only in 1965 the voting rights for african americans would be actually able to vote in the south.

in 1965, president johnson signed the voting rights act, which aimed to overcome legal barriers that prevented african americans from voting as it was guaranteed by the 15th amendment to the u.s. constitution.