Final answer:
California and Washington implemented different versions of the open primary system in response to the Supreme Court's decision, while Louisiana maintained its closed primary system.
Step-by-step explanation:
In response to the Supreme Court's decision in California Democratic Party v. Jones, California and Washington implemented different versions of the open primary system. California adopted a top-two primary method, also known as a jungle primary, where candidates from all parties compete against each other in the primary and the top two candidates advance to the general election. This allows for the possibility of two candidates from the same party facing each other in the general election. In contrast, Washington adopted a modified open primary system called a pick-a-party primary, where voters must choose a party and can only vote for candidates from that party in the primary.
On the other hand, Louisiana responded to the Supreme Court's decision by maintaining its closed primary system, where only registered members of a political party can participate in that party's primary. This means that voters in Louisiana must be registered as a Democrat to vote in the Democratic primary or as a Republican to vote in the Republican primary.