Final answer:
The federal judiciary has both upheld and struck down various voter identification laws, reflecting a mix of rulings on this issue.
Step-by-step explanation:
The federal judiciary, including the Supreme Court and lower courts, has not upheld voter identification laws in every case nor struck them down in every instance. Instead, the correct answer is c. Upheld some voter identification laws and struck down others. In 2013, the Supreme Court repealed several aspects of the 1965 Voting Rights Act, resulting in some states adopting voter identification laws that had previously been blocked.
The ruling in Crawford v. Marion County Election Board (2008) found Indiana's voter identification law constitutional, but the decision did not close the door on future challenges. Several states have implemented voter ID laws, some of which have been contested in courts with varying outcomes. As such, new voter identification laws have been enacted, with some subsequently facing legal challenges, illustrating the judiciary's mixed rulings on this matter.