He is the second to resign during German Chancellor Angela Merkel's regime and it is seen as a blow to her and her party, one year prior to the next election cycle.
The role of Germany's President is chiefly a ceremonial one. Whoever fills the job is expected to act in a way that is above partisan politics and provide an ethical and moral compass.
Wulff's resignation became necessary after his ethics were challenged. Investigators have found enough evidence to have forced Wullf's hand. The news gets worse for him as the Parliament is being asked to lift the cover of immunity to prepare for possible charges against him.
The specifics revolve around Wulff's friendships with wealthy supporters in the business and media world and the financial assistance he received from them. These alleged activities occurred during his term as Governor of the regional state of Lower Saxony.
After a high profile divorce and remarriage to a much younger woman in 2008, it is alleged that Wulff took a large loan from the wife of one of his supporters and enjoyed vacations on someone's dime.
Wulff addressed his resignation by taking the high road. "The developments of the past few days and weeks have shown that trust and thus my effectiveness have been seriously damaged, he said. "I have made mistakes, but I was always honest."
Chancellor Merkel had hand picked Wulff to fill the President's slot. A longtime ally in the Christian Democrat party, he was a controversial choice and she expressed regret in accepting his resignation.
He was forced to go through multiple rounds of voting prior to emerging as the winner and the process was said to have damaged Merkel's administration, but she stood beside Wulff during the process.
The President is chosen by a special group that combines a number of national legislators and regional governments representatives. Wulff became president after Horst Koehlerb, another ally of Merkel resigned after controversial remarks.
It is expected that the Chancellor will ask for help from the opposition party in Parliament to avoid another round of dissatisfaction and political fighting. It makes political sense to do so as Merkel is on the front lines of the eurozone debates and decisions regarding the financial crisis in Greece.
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