Lobbying and political contributions don’t increase a company’s profits, a new academic study suggests — they mostly just enrich the CEO.

This is the latest thinking on questions that vex Washington: What is the return on investment in lobbying? Does a PAC contribution actually pay for itself?

For every company that hits the jackpot after a lobbying campaign, scores of others end up throwing away money on lobbyists.

There are so many cases of a lobbyist winning an earmark, or a PAC contribution immediately preceding a subsidy, that it’s hard not to see politics as a good investment. But these anecdotes tell us only that lobbying and donating to politicians sometimes pay off immensely.

But for every company that hits the jackpot after lobbying campaign, scores of others end up throwing away money on lobbyists — and scores of executives whose PAC contributions don’t help the company a bit.

Business professors Russell Sobel and Rachel Graefe-Anderson of the Mercatus Center at George Mason University collected the data and dug into the bigger question: Do lobbying expenditures and PAC contributions increase corporate profits, on average?

Their answer: No — except on Wall Street.

“[W]e find little evidence to support the idea that political activity undertaken by corporations leads to improved performance for firms and their shareholders," the authors write.

The only exception was the banking and financial sectors, where they found “positive and significant correlations between firm lobbying activity and three measures of firm financial performance,” including return on investment and return on equity.

Lobbying spending reported to Congress has increased over the past decade. Companies reported spending $20.2 billion in the past six years according to data from the Center for Responsive Politics (since 2008, when the bailout barrage began), compared to $14.04 in the previous six years. Adjusted for inflation, that's still a 25.6 percent increase -- and it doesn't even count the jump in non-disclosed lobbying or quasi-lobbying expenditures.

PAC spending is also climbing: $1.4 billion in the 2012 election, up from $838 million (in 2012 dollars) in the 2000 election.

With all this extra money pouring into politics, who’s benefitting?

The most obvious beneficiaries (the study doesn’t explore this angle) are the lobbyists, quasi-lobbyists and the future lobbyists — that is, politicians.

When government grows, this induces companies to spend more on lobbying. The lobbyists then have a personal incentive to lobby for more government, which in turn makes politicians and bureaucrats more valuable to corporations. The revolving door spins, government grows and all the insiders get rich.

Besides the lobbyists, the Mercatus study suggests, the CEOs also profit from their companies’ political activities. When Sobel and Graefe-Anderson crunched numbers, conducted regressions, and controlled for firm size, industry and other factors, they arrived at data “suggesting that any benefits gained from corporate political activity are largely captured by firm executives.”

In short, when a CEO and a lobbyist decide to get their company more involved in politics, the CEO and the lobbyist benefit, while not helping the company.

Pfizer, in a 2010 corporate filing, justified CEO Jeffrey Kindler's $300,000 compensation bump by listing his various accomplishments, noting: “These efforts included constructive participation in the U.S. legislative process to advance Pfizer's goals of achieving a more rational operating environment.” In other words, Kindler lobbied to help shape Obamacare, which Pfizer later supported.

The Mercatus study tells of failed solar-panel maker Solyndra: “After receiving government funds, several top executives at the firm, including the CFO and two vice-presidents, were given bonuses ranging from $44,000 to $60,000 in both April and July … just months before the company filed for bankruptcy.”

Often, top executives reap non-pecuniary benefits. Buddy up to a popular President like Barack Obama circa 2009, and suddenly you're a mini-celebrity -- getting invited to state dinners at the White House, serving on presidential commissions and so on. CEOs want to be loved, too, and if you make yourself a “green” company and start pushing for “socially conscious” legislation and “solutions in Washington,” the press starts covering you as a good citizen, not merely a capitalist.

Economists often speak of the “principal-agent problem.” CEOs and lobbyists are supposed to be agents, working for the company’s owners (the principals) — or the shareholders in the case of a public company. But agents’ interests sometimes diverge from the principals’ interests. In those cases, if the agents have much more information and ability to act, they will at times undermine the principals and benefit themselves.

In common parlance: Without providing a broader economic benefit, politics enriches the insiders.

Timothy P. Carney, The Washington Examiner's senior political columnist, can be contacted at tcarney@washingtonexaminer.com. His column appears Sunday and Wednesday on washingtonexaminer.com.