35 ILCS 200/20-95

The power and duty to collect any tax due and unpaid shall continue in and devolve upon the county collector and his or her successors in office, after his or her return and final settlement, until the tax is paid. The warrant attached to the collector's book shall continue in force and confer authority upon the collector to whom the warrant was issued, and upon his or her successors in office, to collect any tax due and uncollected thereon, although the books have been returned, or the tax carried forward into any other book.