The Harter Act was designed to protect American shipping companies from liability involving damaged or lost cargo. English companies were allowed to add clauses to the bills of lading that protected them from responsibility in certain events if goods were damaged. The Harter act was designed to give the same protection to American shippers. It only applies to domestic shipping. If applies to international shipping, the Harter act must be mentioned in the bill of lading. So, The Harter Act:

If the owner of any vessel transporting merchandise or property to or from any port in the United States of America shall exercise due diligence to make the said vessel in all respects seaworthy and properly manned, equipped, and supplied, neither the vessel, her owner or owners, agent, or charterers, shall become or be held responsible for damage or loss resulting from faults or errors in navigation or in the management of said vessel nor shall the vessel, her owner or owners, charterers, agent, or master be held liable for losses arising from dangers of the sea or other navigable waters, acts of God, or public enemies, or the inherent defect, quality, or vice of the thing carried, or from insufficiency of package, or seizure under legal process, or for loss resulting from any act or omission of the shipper or owner of the goods, his agent or representative, or from saving or attempting to save life or property at sea, or from any deviation in rendering such service.

Source: verbatim from the US Code ch. 105, Sec. 3, 27 Stat. 445. as found in 1893, the year of passage of the act.

In essence the law makes the following points in protecting ship owners from liability. The following circumstances are those that the shipper is not liable for if damage or loss occurs to the cargo:

Four circumstances were recognised by everyone before the passage of the act:

  • Acts of God.
  • Destruction by pirates or countries at war.
  • Inherent vice.
  • Fire (not listed in Harter, rather in the Fire Statute of 1851, but implied in Harter).

The following are specific to the Harter Act only:

The shipper can only enjoy the above ten immunities if he fulfills three requirements.

Along with numerous websites, I used Marine Cargo Operations, by Saurbier and Meurn.