He has been forced to resign and is on trial in the country's largest postwar bribery scandal. But former Prime Minister Kakuei Tanaka paradoxically remains a powerful force in Japanese politics.
Ostensibly he quit the ruling Liberal Democratic Party (LDP) after his arrest. But he remains in parliament, and in many ways his influence in the LDP has never been greater.
His five-year-old trial on a charge of receiving over $2 million for helping Lockheed Corporation sell aircraft in Japan is not expected to end until next year. But the cocky, self-made construction millionaire has been expecting to be acquitted and is preparing for a political comeback.
That is, he was until he received some powerful shocks in recent weeks that many observers say have virtually clinched his conviction.
The prosecution's case is that Mr. Tanaka, during a 1972 meeting in Honolulu with then President Richard Nixon, promised to do his best to encourage sales of Lockheed aircraft in Japan to help rectify a bilateral trade imbalance.
Later, the Marubeni Trading Company, Lockheed's sales agent here, allegedly paid Mr. Tanaka 500 million yen (over $2 million) for his help. The transfers were alleged to have been supervised by Toshio Enomoto, then Mr. Tanaka's private secretary.
The repeated denials of both men were challenged at the end of October when Enomoto's ex-wife took the stand to state categorically that her former husband had once confessed his involvement and asked her what he should do to avoid punishment.
Even more damaging to Mr. Tanaka has been the conviction, in a related trial, of his close friend, Kenji Osano, a business tycoon known to the Japanese as ''kuromaku'' (literally ''behind the black curtain''; in other words a behind-the-scenes political manipulator).
He was sentenced to a year in jail for perjury. The court found that in Diet cross-examination in 1976 he had falsely denied receiving $200,000 from a Lockheed executive to help sell the Tristar airliner to All Nippon Airways, in which he is a major shareholder.
Although that verdict is being appealed, observers said its importance was that it confirmed the prosecution's basic case, with worrying implications for Tanaka.
LDP officials can hardly be happy at seeing the party's image dragged through the mud, but they haven't lost many votes yet. The party has been in power for 30 years despite numerous bribery scandals.
Can the Lockheed case be a turning point for cleansing Japanese politics? The influential daily newspaper Asahi has had its editorial doubts, pointing to Tanaka's continued influence in the LDP and moves to reinstate government officials suspected of involvement in Lockheed but not indicted. It quoted the Diet statement last week of Justice Minister Seisuke Okuno attacking the prosecutors for calling Mr. Enomoto's ex-wife as a witness.
Tanaka's political resilience amazes many people. His faction claimed the allegiance of 70 to 80 LDP men at the time of his arrest in 1976. In the last year there has been a rush to join his camp, and the former premier has been able to boast of having more than 150 supporters out of 421 LDP Dietmen.
Tanaka can still exercise great influence. One close aide, Susumu Nikaido - who narrowly escaped indictment in the Lockheed case - is expected to be named party secretary-general in the next Cabinet reshuffle.