Experts have blamed the captain of the Costa Concordia cruise ship for the disaster in which 32 people died.
They also faulted the crew and ship owner for a series of blunders, delays and security breaches.
The Costa Concordia ran aground and capsized on January 13 off the Tuscan island of Giglio after Capt Francesco Schettino took it off course in a stunt. He is accused of causing the shipwreck, manslaughter and abandoning the ship before all passengers were evacuated.
Eight other people are also under investigation, and the court in Grosseto ordered the expert investigation to help it determine which if any should be put on trial. A hearing is scheduled for next month.
The experts said a series of problems hampered the response to Schettino's manoeuvre and contributed to the botched evacuation: crew members bungled directions, didn't understand orders and weren't trained or certified in security and emergency drills.
And they said ship owner Costa Crociere delayed alerting coastal authorities about the emergency - a charge Costa denied today.
In a statement, Costa said by law it was Capt Schettino who was supposed to have alerted authorities about the accident, and that the captain assured the Costa crew on land that he had done so. And regardless, Costa said, Capt Schettino's reports to Costa's headquarters were so delayed, partial and confused that the company couldn't discern how serious the emergency was. And Costa firmly rejected the experts' claims that the crew was unprepared for emergencies, saying the "alleged defects in the certifications of some of the crew" didn't affect the evacuation.
Passengers described a confused and delayed evacuation, with many of the lifeboats unable to be lowered after the boat listed to one side. Some of the 4,200 aboard jumped into the Mediterranean and swam to the island, while others had to be plucked from the vessel by rescue helicopters hours after the collision.
Some passengers said they were shocked to see Capt Schettino already ashore when they were being evacuated. He claims he helped direct the evacuation from the island after leaving the ship.
Work has begun to remove the tons of rocky reef embedded into the Concordia's hull, a first step in plans to eventually tow the wreck away from the island. The whole removal process is expected to take as long as a year.
www.costacruises.co.uk/ (Costa Cruises)