Prosecutors say the veteran politician engaged in a persistent pattern of misusing public money and campaign funds for things like parties, golf outings and gambling.
Shirakawa has agreed to sign documents admitting to 10 counts of violating the political reform act by spending campaign funds for personal use.
The District Attorney's office says Shirakawa faces up to one year in county jail and $50,000 in fines when he is sentenced at a later date.
