Explain the practice and importance of Judicial review in the US (10)

Judicial review is an exclusive power of appellate courts, most importantly the US Supreme Court (SCOTUS). It is able to  overturn any judicial ruling from another court (at federal or state level) or to strike down any executive action or law deemed unconstitutional. This is not a constitutional power - the constitution is vague and open to interpretation in regards to the judicial branch of government -  but a power that the court granted itself. This happened in the case of Marbury vs Madison in 1803, in which SCOTUS overturned congressional legislation. Judicial review is carried out any time that SCOTUS makes a ruling in a case taken on appeal, which is the vast majority of it's cases, and is done so by a vote of the 9 justices. Their vote should in theory reflect the fundamental authority of the constitution and thus uphold constitutional sovreignty in the US, which makes judicial review incredibly important. For example, in the landmark case Brown vs the Board of Education, SCOTUS ruled that segregation on the principle of 'Separate but equal' violated the 14th amendment

Judicial review is also important in the context of federalism, and the balance of power between the central government and the state governments in the United States. Many who would support a small central government see judicial review as an encroachment on the rights of states to make their own laws. Due to the loosely-defined relationship between central and state powers in the constitution, US history has seen an overall growth in the power of the federal government at the expense of the states, and an increasingly interventionist judiciary is part of this. Any act of judicial review applies to the whole US. This problem is exacerbated by claims that SCOTUS is becoming politicised, largely due to the highly politicised appointments process in which candidates are selected by the President and confirmed by the senate. Thus, a politicised judiciary may carry out judicial review to impose a partisan or ideological ruling on the whole country. Critics of the 2015 Obergefell vs Hodges case, which legalised same-sex marriage, argue that the ruling both increased the power of federal government and furthered a liberal interventionist agenda. Thus judicial review is important in granting both the judiciary and the federal government extensive power.