Japan's Diet convened last week, the first parliamentary session with the new government in charge and the once-formidable Liberal Democratic Party (LDP) in opposition. The main order of business will be to debate the fiscal 2010 budget, the first compiled by the new government.

You might think that there would be plenty to debate about a national budget that exceeds US$1 trillion for the first time in Japan's history and requiring record amounts of deficit borrowing might be grist for serious public discourse.

One might think that the new government's plans to substantially raise social welfare spending by giving money to families with young children and ending tuition payments for public high schools in the face of falling tax revenues might provide plenty for the opposition to chew over.

It might be expected that the new government's dithering over the issue of moving some American forces from Okinawa might give the opposition an opening for accusing the new government of endangering the security alliance with the United States.

You might think all of those things, but you would be wrong. The first day of debate in the House Budget Committee, where the leaders of the two main parties came face-to-face for the first time since the August 30 election swept the Democratic Party of Japan into power, was taken up almost entirely by scandals.

Sazukazu Tanigaki, the post-election leader of what is left of the LDP along with his colleagues, spent most of their allotted time grilling Prime Minister Yukio Hatoyama over alleged undeclared political donations to his campaign organization.

It has been alleged that Hatoyama's mother, an heiress to the Bridgestone tire fortune, funneled millions of yen to his fundraising body during the past decade. Some of the money was said to be disguised as coming from other sources to get around individual donation limits. Two of the premier's former aides have been indicted for infractions of the Political Funds Control Law.

When the news of Hatoyama's mother's donations first surfaced well before the August 30 election, Hatoyama said he thought they were loans, but nevertheless paid about JPY 500 million in back gift taxes. The premier proclaimed his innocence at the budget hearing, saying that if "different facts emerge" he had no right to wear his Diet member lapel button.

Tanizaki saved some of his fire for Ichiro Ozawa, the secretary general of the DPJ. Not being a member of the cabinet, Ozawa was not present to hear it, but his looming presence as the No. 2 man in the government was strongly felt. The next day Ozawa voluntarily submitted to an interview from the officers of the Tokyo Public Prosecutors office.

This particular scandal centers around JPY 400 million that he provided to his political fund raising organization and which was used to purchase a vacant lot for use as a dormitory for party secretaries, and other aides. The fund raising body supposedly failed to report the funds as required.

Just days before the Diet convened, the public prosecutors arrested three of Ozawa's former aides, including Tomohiro Ishikawa, now a freshman DPJ member of parliament, before the parliament's convening would have given him parliamentary immunity from prosecution.

Ozawa was forced to step down as leader of the party last May for an unrelated scandal involving supposed violations of the campaign fund raising laws. In this instance, the defiant Ozawa said he had no plans to resign his current party post. He had loaned the money to the committee from his own personal funds, he said.

The opposition is expected to keep pushing these scandals. The party is far more comfortable with this subject than challenging the government on its policies. After all, it had to withstand many, many "money politics" scandals during its half century in power. It is something that they understand intimately.

The experience of being in opposition is new for the LDP, and it has not yet found its voice. During the election, it tried feebly to oppose some DJP proposals such as the child allowance measure, as being fiscally unsound but the arguments never seemed to gain much traction.

In their hearts, many members of the new government believe that the actions of the public prosecutors are politically motivated. They see the accusations not as a simple corruption scandal but as a kind of morality play – a clash of the "old order", represented by the public prosecutors, against the "new order" of the government.

From their point of view, it is another example of unrestrained power invested in unelected bureaucrats, which they were elected to end. On the other hand, they know it is not politic to voice such feelings too loudly, since most of the public sees the public prosecutor's office as being made up of disinterested tribunes of good government.

Hatoyama took considerable flak for suggesting at the budget meeting that Ozawa should "fight on" Almost immediately he had to backpedal that he had not meant to attack the prosecutors or influence the investigations.

This all comes against the background of the looming general election in July when half of the upper house comes up for re-election. The governing party badly wants to win this election and obtain a clear majority, unencumbered by the need to ally with smaller parties to control the Diet.

So if the opposition forces Ozawa out of his party post, it would be a major coup. He is, after all, by far the DPJ's best election technician. It is widely known that more than 100 members of the Diet freshman class were recruited and groomed by Ozawa personally before the August 30 election.