It isn't difficult for political candidates to find controversy. Often all it takes is a perceived willingness to deceive the media or voters. Republican candidate Mitt Romney, for example, found himself in hot water earlier this year for his reluctance to release his 2010 tax returns. Few were bothered by his wealth, but the impression that he was hiding something had threatened to become damaging.

In Germany, candidates tend not to be nearly as well-heeled as their American counterparts, but income -- and candor about earnings -- is just as important. That, at least, is the lesson currently being learned by newly minted Social Democratic candidate for chancellor Peer Steinbrück . Formerly Chancellor Angela Merkel's finance minister in the dark days of the global crisis, Steinbrück has spent the years since his 2009 departure from Merkel's cabinet as a simple parliamentarian -- and as a highly paid orator on the lucrative speaker's circuit.

Earning income in addition to the standard German parliamentarian salary of €95,520 ($123,670) per year is not illegal. There is also a requirement that lawmakers report to the parliamentary president how much extra cash they make.

Peddling Influence?

The public, however, is not made privy to those filings. Instead, parliamentarians are placed into one of four categories designating roughly how much they make in addition to their salaries. Steinbrück, as it happens, is in the top category, reserved for those who make an extra €7,000 per month -- or more. And it is the "or more" part that has led to current questions about Steinbrück's wealth.

Few believe that Steinbrück has become Romney-rich since his time in the Finance Ministry -- estimates regarding his total annual earnings tend not to exceed €1 million and are generally much less. But, as in the US, it is not the amount of money that matters so much as how honest one is about owning up to it. And, in Steinbrück's case, there have been several calls in recent days -- from all major political parties including his own SPD -- for him to fully disclose the amount of his additional earnings.

And the provenance. Some politicians, particularly from the conservative camp, have sought to raise suspicions that Steinbrück's speaking engagements amount to peddling the influence he gained from having been a highly respected finance minister. "The impression could be created that Steinbrück is the darling of the finance industry," said Alexander Dobrindt, general secretary of the Christian Social Union and an important Merkel ally, in an interview with the conservative daily Die Welt. "He could simply say how much money he has really received from the finance industry since leaving the Finance Ministry and everyone could arrive at their own objective verdict."

Steinbrück himself had long been silent on the issue except to say that he has fulfilled reporting requirements and will no longer hold paid speeches now that he is the SPD's official candidate. On Thursday, however, he blasted his critics in Die Welt. "It is clear that my critics hope to damage my personal credibility," he said. "They won't be successful."

German commentators on Thursday have their say.

Center-left daily Süddeutsche Zeitung writes:

"In the debate over Steinbrück's speaking engagements, CSU head Horst Seehofer said that those who demand full transparency from the banks shouldn't be surprised when transparency is demanded of them as well. Seehofer, though, shouldn't act as though he caught Steinbrück in an act of deception. The SPD chancellor candidate doesn't need to fulfill the demand because he has already done so. He reported his list of clients and earnings to parliament as required by law. There isn't even the smallest of hints at a conflict of interest, particularly given that Steinbrück has spent the last several years in the opposition."

"Those journalists who go on about a 'huge controversy' and 'ongoing critique' should make sure that they weren't rented out recently by an industry association as a podium discussion moderator. Conflicts of interest? They aren't only reserved for politicians."

Center-right daily Frankfurter Allgemeine Zeitung writes:

"As candidate, Peer Steinbrück has said he will no longer hold paid speaking engagements…. But the left wing of the SPD is not satisfied. They are demanding that he publicize his earnings. It is no secret that those in the left wing of the party are not fans of Steinbrück, and now they are showing him, at the very beginning of the campaign, that he will not be spared their critique. Steinbrück countered that he has fulfilled the reporting requirements made of parliamentarians. He must do no more, nor should he."

Left-leaning Berliner Zeitung writes:

"It is a completely standard and legitimate practice that politicians earn money from speaking engagements. And Steinbrück, known as an excellent public speaker, reported all of his activities as required by law. He only received money from companies. He required no payment from associations, charities, schools and universities. It is also believable that he donated a part of his earnings."

"Still, his behavior leaves somewhat of a bad taste. We have known since the spring of 2011 that (he was in the running to become the SPD's candidate for chancellor)…. For reasons of political hygiene, Steinbrück should have reduced his speaking engagements starting then."