The main police investigator in a corruption case involving former German President Christian Wulff took to the stand in Hanover on Thursday, without providing any evidence that appeared to interest the presiding judges.

"The interrogation today did not produce anything truly surprising," Judge Frank Rosenow said. The court said that the next official appointment, on January 9, where another police investigator is due to testify, would be the last day in which evidence was submitted to the court.

The defense went a step further, offering to issue their summation on the same day and suggesting another hearing date, believed likely to be the last, on January 22.

Two weeks ago, the court issued an interim conclusion suggesting that the trial be dropped, saying there was currently no proof that Wulff had accepted favors while in office. The prosecution and defense both responded by saying they wanted the trial to be completed.

The case pertains to Wulff's relationship with businessman David Groenwald, during his time as premier of the state of Lower Saxony, his last political post before becoming president.

Wulff is accused of promoting one of Groenwold's film projects with senior management at engineering giant Siemens, with the prosecution alleging that he did so after the businessman footed some of his expenses incurred at the 2008 Oktoberfest. The alleged bribe, of sorts, was worth a total of 753.90 euros ($1,030 at today's exchange rate).

Wulff resigned in the aftermath of the accusations when the story came to light in early 2012, citing a loss of public trust. One of the largest headlines of what became known as the "Wulff Affair" or "Causa Wulff" in the press was an angry voicemail message about scandal that the then-president left for the editor-in-chief of the mass-circulation Bild daily newspaper. This message arguably became a more notorious element of the "Wulff Affair" than the initial corruption allegations leveled against the president.

msh/pfd (AFP, dpa)