(CNN) -- The U.S. Coast Guard, champion of boating safety everywhere, is to blame for a tragic 2009 accident that killed an 8-year-old boy during a holiday boat parade in San Diego Bay, a federal safety board said Tuesday.
The National Transportation Safety Board said the Coast Guard crew's excessive speed caused the crash between the crew's 33-foot patrol boat and a 24-foot Sea Ray. The crash killed the child, Anthony DeWeese, and seriously injured four of 12 others on the recreational boat.
At the time, the patrol boat was responding to a reported grounding, which the NTSB called a non-emergency. It was cruising at least 19 knots, or roughly 22 miles per hour -- far in excess of the 8 knots prudent for the conditions, the NTSB said.
"The Coast Guard is an organization that traditionally fills the role of rescuer," NTSB Chairman Deborah A.P. Hersman said. "It is especially sad that a family night of celebration in the Bay ended in tragedy because of a coxswain's poor judgment and the Coast Guard's ineffective oversight of vessel operations."
The Coast Guard said Tuesday the NTSB's findings aligned with its own investigation, and that it has taken steps to prevent similar accidents.
"We owe it to the DeWeese family, the memory of Anthony, and the public we serve, to learn all we can from this tragic accident," said Coast Guard spokesman Lt. Cmdr. Christopher O'Neil. "We take very seriously our role as the nation's maritime safety agency and we're profoundly saddened by the loss of life in an accident involving one of our crews."
The collision occurred at night, during a holiday event known as the Parade of Lights.
The patrol boat struck the Sea Ray from behind, according to the NTSB. None of the Coast Guard crew was injured. Three of the five crewmembers on the Coast Guard boat, including the operator, refused to be interviewed by NTSB investigators, the NTSB said.
The NSTB said the Coast Guard's lack of oversight of its small boat vessel operations contributed to the accident. The Coast Guard's San Diego station lacked an effective oversight system to monitor vessels on patrol, it said. And the station's officer of the day, who was on the boat, did not advise the coxswain to slow down.
The NTSB called the speed excessive given the prevailing darkness, background lighting and heavy boat traffic in the area.
Four Coast Guardsmen on the patrol boat were court martialed or faced non-judicial punishment.
In March, the coxswain was found guilty of dereliction of duty for failure to perform a risk assessment, and was sentenced to three months confinement and reduced in rank.
A petty officer 2nd class pleaded guilty to dereliction of duty and was reduced in rank.
In January, another petty officer received a letter of reprimand.
The case of one crewman charged with dereliction of duty was dismissed because of insufficient evidence at a non-judicial hearing.
A fifth Coast Guardsman who was on the boat as a trainee was not charged.
The Coast Guard said that as a result of a review of boat accidents, it has made changes to improve its operations, including increased navigation training requirements for boat crews. It also is ensuring that stations have the most suitable boats to carry out local missions.
The Coast Guard said in the past five years, during 2.6 million boat hours, there have been three Coast Guard boat-related accidents resulting in fatalities. In addition to the San Diego collision, a Coast Guard member was killed in March 2007 after being ejected from a patrol boat near Seattle. Another Coast Guardsman died in October 2010, during a training mission in Virginia after he fell into the water while transferring between a small patrol boat and a cutter.