The National Police Agency began using a database Friday to bar yakuza and other people who have participated in underworld syndicates over the past five years from opening trading accounts at securities houses to keep them out of the financial markets.

If a potential client is found listed in the database, the Japan Securities Dealers Association will consult with the regional police department associated with the client’s address and confirm whether that person is a yakuza or has been part of the mob.

Without the database, the onus for ferreting out suspicious clients fell on the brokerages themselves, forcing them to develop their own databases and call the police to determine whether they had underworld ties.

The JSDA enforces an internal regulation that bans member houses from engaging in trade with “antisocial” forces.

Unlike the old days, when yakuza were mainly involved in blue-collar crimes, today’s crime syndicates have become more sophisticated by incorporating themselves and investing in the financial markets to generate funds for shady activities. They also use white-collar methods to launder “dirty” money through their now “legitimate” corporate activities.