The International Police Force, also known as the Local Law Enforcement, is a law-enforcedment body established by the United Nations. One of its tasks is to eliminate the knowledge and use of Black Technology by seizing technological artifacts and arresting people who use them.
It is also responsible for the issuance of bounty lists under the command of the UN. The IPF is also in charge of monitoring special citizens like the Japanese and keeping them inside colonies. Nations can request the IPF for assistance when faced with internal problems like assasination threats against leaders. In the manga Guilty Gear Xtra, the IPF coordinated with Zepp to destroy the the falling Gear airship.
It is shown in the Guilty Gear X Drama CD that it is corrupt. Ky Kiske, who is a high ranking officer, is even investigating his own superiors. It is implied in the drama that the police force isn't effective enough to mitigate problems like piracy and black market trading.