The cause of Shoichi Nakagawa's death was under investigation, a spokeswoman for the Tokyo police said. His body was found by his wife in the bedroom of their Tokyo home, she said on condition of anonymity due to police policy.

The 56-year-old Nakagawa caused an uproar when he appeared to be drunk at a news conference during a meeting of Group of Seven financial leaders in Rome in February. International news programs repeatedly played footage of Nakagawa slurring his speech and looking sleepy.

More odd behavior followed when he visited a museum at the Vatican after the news conference. He touched exhibits and set off an alarm after entering an off-limits area.

The trip was widely seen as a major embarrassment for the Japanese government.

Nakagawa stepped down as finance minister shortly afterward, denying he had been drunk and blaming cold medicine. But the opposition demanded his resignation.

Nakagawa had been a longtime lawmaker from the northernmost island of Hokkaido with the Liberal Democratic Party, which had ruled Japan almost continuously for the last half-century. He lost his seat in parliament in Aug. 30 nationwide elections in which the Liberal Democrats lost to the Democrats, who now rule Japan in a coalition.