Factbox - Legal action over Alabama's Jefferson County debt

(Reuters) - Alabama's Jefferson County is fighting to avert bankruptcy over a multibillion-dollar debt it accumulated through bond transactions to finance the upgrade of its sewer system.

Controversy over the debt has spawned a host of lawsuits and legal actions as county officials, regulators and people involved in the transactions seek to assign responsibility and negotiate its consequences.

Following is a list of some of the most significant lawsuits over the county's debt and a brief explanation of why each case matters:

LARRY LANGFORD - The former mayor of Birmingham was sentenced to a 15-year prison term March 5 after conviction in federal court in October on 60 counts of fraud, corruption and bribery. Charges related to his tenure as president of Jefferson County Commission from 2002-2007 when the county ran up the sewer debt.

Langford's conviction along with that of lobbyist Al LaPierre and investment banker William Blount, both of whom pleaded guilty, establishes that corruption played a part in the initial debt. It also shed light on transactions between the three men and representatives of major creditor banks.

Blount and LaPierre were sentenced to four-year prison terms.

SEC SUIT - The U.S. Securities and Exchange Commission settled with J.P.Morgan Securities Inc in December for more than $720 million over unlawful payments in the bond financing.

The bank said it would forfeit $647 million claimed from the county in unpaid swap termination fees as well as pay a $25 million penalty and $50 million to the county.

The SEC also charged two former managing directors of JP Morgan Securities, Charles LeCroy and Douglas MacFaddin, with more than $8 million in undisclosed payments to close friends of certain Jefferson County commissioners.

OCCUPATIONAL TAX SUIT - The Jefferson County tax was found to be unconstitutional, following a class action lawsuit file by a county resident, and county court Judge David Rains ordered Jefferson to repay taxpayers $48 million.

The county has appealed to the state Supreme Court to challenge the figure.

JEFFERSON COUNTY SUIT - The county in December sued JPMorgan Securities and JPMorgan Chase for punitive damages and compensation over the accumulation of its debt.

It also sued Langford, LaPierre and Blount as well as LeCroy and MacFaddin and as many as 50 unnamed parties.

The suit claims the parties conspired to profit with interest rate swaps to the detriment of the county.

JEFFERSON COUNTY RECEIVER - A federal judge in Alabama told Bank of New York Mellon last June to refile in state court a suit aimed at forcing the appointment of a receiver to manage the revenue from Jefferson County's sewer system.

The county filed a motion in state court in December seeking to get the bank's new lawsuit dismissed, but Judge Albert Johnson on December 31 denied the motion, allowing the suit to continue.

Creditors want a receiver who could raise rates and would determine the extent to which revenue is used to repay debt. The county is resisting that legal structure.

(Reporting by Matthew Bigg, Verna Gates and Melinda Dickinson; Editing by Tom Brown and Editing by Kenneth Barry)