It may not be possible to appoint Yisrael Beiteinu chairman Avigdor Lieberman as finance minister - a possibility that had been discussed during the coalition talks of the past two days - because the Tax Authority, which is part of the Finance Ministry, was involved in the criminal investigation against Lieberman.

The ongoing investigation already prevents him from heading either the public security or the justice ministry, since they oversee the police and the prosecution, respectively, and it would be improper for a minister under investigation to oversee the organizations responsible for deciding his case. The Finance Ministry, in contrast, would not normally be a problem, and sources involved in the coalition talks said that Lieberman did demand this portfolio, along with the Housing Ministry, in his talks with Likud chairman Benjamin Netanyahu. But the fact that the Tax Authority was also involved in the Lieberman probe may throw a monkey wrench into this idea.

The authority declined to comment, saying it does not discuss ongoing investigations. Yisrael Beiteinu also declined to comment, saying that to do so might be construed as an attempt to obstruct the investigation.

Lieberman himself flew to Belarus Thursday, thereby quitting the country at a critical stage in the coalition talks. Politicians from across the political spectrum were united in terming this a blatant attempt to flaunt his power: Yisrael Beiteinu, having won 15 seats and become the third-largest party in the Knesset, is the indispensable partner without whom neither Netanyahu nor Kadima chairwoman Tzipi Livni can form a government. Although the party has a negotiating team, it has no authority to make decisions without Lieberman.

Lieberman has yet to announce whether he will support Netanyahu or Livni for the premiership, and some politicians speculated that he would ultimately recommend neither to President Shimon Peres: Instead, he would recommend himself.

Sources involved in the Lieberman-Netanyahu talks reported that Lieberman also wants Justice Minister Daniel Friedmann, who was appointed by outgoing Prime Minister Ehud Olmert, to retain his post. Friedmann, who is not a Knesset member and is not formally affiliated with any party, would fill one of the ministerial positions to which Yisrael Beiteinu is entitled.

The investigation of Lieberman heated up two and a half weeks before the election, when the police arrested seven suspects, including his daughter Michal and his attorney Yoav Many.

In April 2007, Haaretz published an investigative report on M.L.-1, a business consulting firm set up by Michal Lieberman in 2004, when she was 21 years old. She was listed as the sole shareholder, but one of the company's two official addresses was her father's house in the West Bank settlement of Nokdim.

Between 2004 and 2007, the company received NIS 11 million from anonymous overseas sources in exchange for "business consulting." Avigdor Lieberman received a salary of over NIS 2.5 million from M.L.-1 during 2004-06, when he was not serving in the cabinet or Knesset, and was thus legally entitled to do so. But the company itself remained active even after Lieberman rejoined the Knesset in March 2006.

The police suspect Lieberman of money laundering, fraud and breach of trust. However, the investigation was delayed for over a year, from April 2007 until August 2008, because of lawsuits filed by Lieberman and his associates claiming that various documents the police wanted to examine were protected by attorney-client privilege. Only after the courts finally rejected these suits were police able to begin studying the documents.