Basically by getting on the game and leaving bugs and stuff like that.

A player, 'Trili' got on, found the network password and information, and cleared the database causing the game to crash for several weeks.

You have other people who get on with numerous accounts, or use unethical methods to get what they want. Though it is a mafia-based game, there are still methods to go by. Generally players who fail to do so are found dead in the streets.