Final answer:
Interest groups challenge existing policies and laws through litigation, influencing the judiciary with amicus curiae briefs and playing a larger role in political education and government monitoring.
Step-by-step explanation:
Interest groups use judicial strategies, such as litigation, to challenge existing policies and laws within the court system. This is one of the avenues through which interest groups influence public policy, often by taking legal action to oppose or support specific laws. Litigation can range from filing lawsuits in lower courts to appealing cases to the Supreme Court, as seen with the case of Sierra Club v. Trump, where interest groups challenged presidential use of executive power.
Interest groups also lobby the judicial system through mechanisms like amicus curiae briefs, offering their expertise and viewpoints to inform judicial decision-making. This form of lobbying is unique because, unlike the legislative process where laws are written and passed, the judicial process involves the interpretation and application of laws. Additionally, while the participation in the litigation and filing of amicus curiae briefs are directed towards influencing court decisions, interest groups are also deeply involved in other activities such as educational campaigns, political participation, monitoring government activity, and shaping issues through the media.