Rescuers work to save a horse trapped in the 2007 double decker truck crash involving Belgian Draft horses. © Robert Schreiner, Newport Township Fire Protection District
» More pictures from the rescue.
The bill proposes a ban on double-deckers being used for horse transport.
Chairman Oberstar spoke eloquently of the dangers horses faced in a series of accidents involving double-decker trailers and commended the bipartisan nature of the legislation.
Representative Leonard Boswell offered an amendment to remove the ban on double deckers from the bill and to simply regulate these vehicles.
He then agreed to withdraw the amendment after several members from both parties spoke strongly against it as undermining the need for an immediate ban.
The legislation would prohibit the interstate transportation of horses in a motor vehicle containing two or more levels stacked on one another.
The bill was introduced by Representatives Mark Kirk and Steve Cohen, and has 70 House co-sponsors.
In addition to Oberstar and Cohen, Representatives John Hall, Phil Hare and Frank LoBiondo also spoke in strong support of the legislation.
"The time has come for Congress to ban double decker trailers for all horses," said Keith Dane, the society's director of equine protection.
"We don't need any more gruesome incidents to know that double-decker trailers are inhumane and unsafe.
"These vehicles are primarily used by the horse slaughter industry for hauling as many horses as possible from auctions to slaughter plants in Canada and Mexico.
"The American public loves horses and this legislation is urgently needed to prevent future tragedies," he said.
Double-decker trailers are designed for animals such as cattle and pigs - shorter-necked species than horses, which require more headroom than double-decker trailers afford.
Horses often throw their heads to maintain balance, and injure easily in such vehicles.
The US Department of Agriculture has stated: "We do not believe that equines can be safely and humanely transported on a conveyance that has an animal cargo space divided into two or more stacked levels."
"It is time that we put an end to the inhumane practice of using double-decker trailers to transport horses," Kirk said.
"Stacking these animals one atop the other in a moving vehicle is simply an accident waiting to happen. It is not only a cruel way to transport horses, but it also puts human lives at risk."
Cohen said: "Using double-stacked trailers is inhumane and cruel. Our bill prohibits any interstate transportation of horses in double-stacked trailers and implements tough civil penalties for anyone caught using such deplorable modes of transportation for horses."
Recent accidents graphically demonstrate the dangers of the double-decker trailers. In 2006, a double-decker truck hauling 41 horses in Missouri crashed, killing 16 horses.
In 2007, a double-decker carrying 59 horses in Illinois struck another vehicle after blowing through a stop sign.
It took five hours to rescue the horses from this mangled truck, resulting in the deaths of nine horses; six died later due to injuries sustained.
In both instances, the design of the trailers caused horses to lose parts of their legs or break their backs. Others were crushed under the weight of other horses falling on top of them.
Congress will soon recess for the summer but returns in September when the bill is now cleared for a vote before the US House of Representatives.