An Australian-British dual national accused of murdering his wife and deliberately sinking their catamaran to disguise the crime was motivated to end their “marital strife” and acquire her estate, US prosecutors have argued.

Lewis Bennett was charged by the FBI with second-degree murder in February this year in relation to the death of his wife, Isabella Hellman.

Bennett and Hellman were honeymooning aboard their 11m catamaran in the Caribbean last May, when Bennett sent an SOS message saying his wife was missing and the vessel was taking on water.

He claims was awoken when the catamaran collided with an unknown object, and was unable to locate Hellman above deck. As the vessel began to sink, Bennett sent a distress signal and boarded a life raft.

He was rescued by the US Coast Guard. Authorities did not find Hellman’s body. Afterwards, the catamaran was discovered capsized off the coast of the Bahamas.

Prosecutors last week asked a Florida judge to admit evidence they claim shows a motive for her alleged murder, and his alleged scuttling of the vessel.

Prosecutor Benjamin Greenberg said Hellman’s family had grown suspicious of Bennett, and bugged her apartment to record the couple’s conversations before her disappearance.

Greenberg said the conversations showed the couple “consistently” fought, adding their conflicts motivated Bennett to commit the alleged crime.

Hellmann’s murder would remove the marital strife from the defendant’s life, allow the defendant to live his life as he pleased, and would enable him to inherit money from Hellmann’s estate, all of which provide strong circumstantial proof that the defendant had a strong motive to murder Hellmann.

Their arguments reportedly included references to a move to Australia.

It was further alleged that Hellman’s potential discovery of Bennett’s stash of stolen gold and silver coins on the vessel may have been a factor in her disappearance. Bennett is currently serving seven months behind bars for smuggling the coins, worth nearly $58,000.

Bennett maintains his innocence over Hellman’s death. He is slated for face trial for the alleged murder in December.

If you or someone you know is dealing with issues around sexual violence or domestic or family violence, you can call 1800 RESPECT on 1800 737 732, the Mens Helpline on 1300 78 99 78, or the Kids Helpline (ages 5 to 25) on 1800 55 1800.

If you are in distress, please call Lifeline on 13 11 14.

Source: BBC
Image: US Coast Guard