In United States v. Harriss, a Supreme Court case in the news because of the recent NAM effort to challenge provisions of HLOGA, the Court discussed lobbying disclosure, as a general matter (citations omitted):

Present-day legislative complexities are such that individual members of Congress cannot be expected to explore the myriad pressures to which they are regularly subjected. Yet full realization of the American ideal of government by elected representatives depends to no small extent on their ability to properly evaluate such pressures. Otherwise, the voice of the people may all too easily be drowned out by the voice of special interest groups seeking favored treatment while masquerading as proponents of the public weal. This is the evil which the Lobbying Act was designed to help prevent.

Toward that end, Congress has not sought to prohibit these pressures. It has merely provided for a modicum of information from those who for hire attempt to influence legislation or who collect or spend funds for that purpose. It wants only to know who is being hired, who is putting up the money, and how much. It acted in the same spirit and for a similar purpose in passing the Federal Corrupt Practices Act — to maintain the integrity of a basic governmental process.

Under these circumstances, we believe that Congress, at least within the bounds of the Act as we have construed it, is not constitutionally forbidden to require the disclosure of lobbying activities. To do so would be to deny Congress in large measure the power of self-protection.

And here Congress has used that power in a manner restricted to its appropriate end.

Justice Jackson dissented:

The First Amendment forbids Congress to abridge the right of the people “to petition the Government for a redress of grievances.” If this right is to have an interpretation consistent with that given to other First Amendment rights, it confers a large immunity upon activities of persons, organizations, groups and classes to obtain what they think is due them from government. Of course, their conflicting claims and propaganda are confusing, annoying, and, at times, no doubt, deceiving and corrupting. But we may not forget that our constitutional system is to allow the greatest freedom of access to Congress, so that the people may press for their selfish interests, with Congress acting as arbiter of their demands and conflicts.

In matters of this nature, it does not seem wise to leave the scope of a criminal Act, close to impinging on the right of petition, dependent upon judicial construction for its limitations. Judicial construction, constitutional or statutory, always is subject to hazards of judicial reconstruction. One may rely on today’s narrow interpretation only at his peril, for some later Court may expand the Act to include, in accordance with its terms, what today the Court excludes. This recently happened with the antitrust laws, which the Court cites as being similarly vague. This Court, in a criminal case, sustained an indictment by admittedly changing repeated and long established constitutional and statutory interpretations. United States v. South-Eastern Underwriters Ass’n, 322 U. S. 533. The ex post facto provision of our Constitution has not been held to protect the citizen against a retroactive change in decisional law, but it does against such a prejudicial change in legislation. As long as this statute stands on the books, its vagueness will be a contingent threat to activities which the Court today rules out, the contingency being a change of views by the Court as hereafter constituted.

The Court’s opinion presupposes, and I do not disagree, that Congress has power to regulate lobbying for hire as a business or profession and to require such agents to disclose their principals, their activities, and their receipts. However, to reach the real evils of lobbying without cutting into the constitutional right of petition is a difficult and delicate task for which the Court’s action today gives little guidance. I am in doubt whether the Act, as construed, does not permit applications which would abridge the right of petition, for which clear, safe and workable channels must be maintained. I think we should point out the defects and limitations which condemn this Act so clearly that the Court cannot sustain it as written, and leave its rewriting to Congress. After all, it is Congress that should know from experience both the good in the right of petition and the evils of professional lobbying.