
Prosecutors are calling for a prison sentence of up to 12 years for Sean Michael McDonald, who killed two people and injured another after his boat collided with their vessel as both boats returned from a Sunday outing at Rum Point in 2019.
McDonald was found guilty on 2 Aug., 2022 of two counts of manslaughter and one count of endangering human life through a reckless and negligent act, following a judge-alone trial.
Former RCIPS police officer Emmanuel ‘Manny’ Brown, 49, and John Turner, 70, a British resident in Cayman, were killed in the night-time collision on 11 Aug. 2019.
The third person on board, a female passenger, was seriously injured when their boat, a Godfrey Hurricane, and the vessel McDonald was piloting, a 32-foot Scarab called the Pepper Jelly, collided near Harbour House Marina in Prospect.
Sitting with his eyes closed and his head lowered into his clasped hands, on Friday 13 Jan., McDonald listened in silence as lead prosecutor Richard Matthews, KC, called for a sentence that would reflect “McDonald’s demonstrable behaviour”, which led to “devastating heartbreak” for the surviving victim, and the families of the deceased.
“The incident has been devasting and catastrophic with ongoing sadness and loneliness,” said Matthews. “The families have had to incur expenses of retaining an attorney and having to sell a family home in light of the loss of income.”

Matthews suggested a starting point of eight years with a sentencing range of six to 12 years for the manslaughter charges, claiming there were several aggravating circumstances which warrant a sentence towards the upper end of the limit.
“A captain of 15 years, the defendant has demonstrated a keen understanding of the dangers posed by his actions, as was evident during his testimony,” said Matthews. “However he chose to act with demonstrable behaviour which was in effect a reckless disregard to what was an obvious risk of death.”
Matthews said, minutes prior to the accident, McDonald was travelling in excess of 35mph in an area that required 5mph for all watercraft users, and at the time of the collision he had sped up further.
“Had he been travelling at the required speeds, and had his vessel not had defective lights this accident could have been avoided,” said Matthews.
He added that McDonald’s failure to report the accident to police more than an hour later was another aggravating factor, as it delayed the amount of time that victims had to be treated.
‘He would do anything to right this wrong’
When offering mitigating submissions on behalf of McDonald, Ben Tonner, KC, told the court his client would “trade places with the deceased in a heartbeat”.
“My client is the first person to recognise this tragic loss,” said Tonner. “His belief, supported by the expert evidence… is that he does not accept criminal culpability of the accident, but he does accept the heartbreak and hurt caused by his actions. He has on many occasions said that if he could go back in time, or even trade places with the deceased, he would do it in a heartbeat. He would do anything to right this wrong.”
When asking that a minimum sentence of four years be imposed, Tonner told Justice Cheryll Richards, there were four mitigating factors present. These include no relevant previous convictions, McDonald’s remorse, the physical injuries McDonald also sustained during the accident, and the ongoing psychological depression he has suffered since the accident.
Tonner then turned his attention to the outpouring of support from families and friends who came forward to write references on McDonald’s behalf.
In one letter, a friend described McDonald as being a shell of himself following the accident, another person described him as a careful and attentive individual while out on the seas, while another person wrote that McDonald had the potential to be a positive leader in the community and had the ability to effect change.
When wrapping up his submissions Tonner said McDonald “is ready to receive his punishment and is genuinely remorseful for the hurt he has caused”.
Justice Richards released McDonald on bail and stated that she would hand down her judgment next week Wednesday.
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The pertinent issue is that he was traveling at 35mph in a 5mph zone.
We see this all the time along the canal where we live, which is posted 5mph. Especially jetskis just tearing along. Overloaded Stingray City charters creating massive wakes in no wake zones.
The marine police do nothing.
Just a matter of time before someone is killed.