This is a powerful tool in the hands of the courts. Noninstitutional Actors Public policy is set by others than those who are formally part of policy making. The media can influence outcomes in policy by defining social reality. This is arguable insofar that not everything the media presents may be factual, although it is assumed that the media makes every effort to report the facts. Policy issues presented in the media can effect the outcomes of legislation, action on the part of the executive branch but less so in the judiciary.
Political parties seek to get their own member selected to influence policy making.
Interest groups seek to influence policy on specific issues. On a larger scale, the party does not seek only a specific issue to press but is outwardly interested in control of the policy process through electoral office holding. Political consultants are those who espouse political savvy and offer their services to those who need it. In so doing, it is possible for the consultant to influence policy by assisting the politician in decision making. The cost of such a person is high and credibility is always an issue to be addressed.