BANGOR, Maine — The trial of a Garland man accused of strangling his girlfriend and then killing her children, aged 10 and 8, in December 2014 because they were witnesses began shortly before noon Wednesday at the Penobscot Judicial Center.

Keith Coleman, 29, who is charged with three counts of intentional or knowing murder and one count of gross sexual assault, has pleaded not guilty.

Coleman was arrested Dec. 21, 2014, in Bucksport and charged in connection with the deaths of Christina Sargent, 36, her son, Duwayne Coke, 10, and her daughter, Destiny Sargent, 8.

The victims’ bodies were found about 9 p.m. Dec. 20, 2014, by concerned family members in the trailer at 12 Paul Road in Garland, where Coleman lived with Sargent and her children.

The jury of 10 men and six women, including four alternates, heard opening statements Wednesday before taking a lunch break about 12:30 p.m. They were selected after being interviewed Monday and Tuesday from a pool of about 80 Penobscot County residents.

Assistant Attorney General Donald Macomber told jurors in his opening statement that Coleman strangled all three victims and sexually assaulted Destiny Sargent before fleeing the scene. Macomber said Coleman used ligatures and clothing to kill them after Christina Sargent ended the relationship and told him to move out.

“After he strangled them, Keith Coleman took Sargent’s van, went down to the local store and bought himself a beer,” the prosecutor told the jury. “Then he went to stay with friends and co-workers in Bucksport [where he was arrested the next day].”

Macomber said the jury would find Coleman guilty on all charges.

Defense attorney Martha Harris of Bangor in her opening statement described Coleman and Christina Sargent’s relationship as long and tumultuous.

“The evidence will show that these crimes most likely were committed by more than one person,” she said. “The ligatures found on the victims contained the DNA of some unknown person or persons.”

She said that jurors would exonerate Coleman.

The trial was scheduled to resume at 1:30 p.m. Wednesday with witness testimony.

Coleman has been held without bail since his arrest.

If convicted, Coleman faces between 25 years and life in prison. The Maine Supreme Judicial Court has ruled that a defendant convicted on multiple counts of murder may be sentenced to life in prison.

If you or someone you know is experiencing domestic violence and would like to talk with an advocate, call 866-834-4357, TRS 800-787-3224. This free, confidential service is available 24/7 and is accessible from anywhere in Maine.

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