The trial of a Massachusetts man accused of stabbing another man in the back during a dispute at a Lebanon horse farm in April 2012 has been postponed until Friday while a New London Superior Court judge considers defense motions to dismiss the case.

Attorney Michael A. Blanchard, who represents Matthew Hanson, 32, of Bourne, Mass., contends that the state police and prosecutor David J. Smith failed to preserve and turn over potentially exculpatory evidence in the case, including a state police dashboard camera recording what Blanchard said contained statements favorable to his client’s case. In his motion to dismiss, Blanchard noted he had filed a motion to preserve the recordings in July 2013 and cited state and federal cases that call for dismissal of a case when the state fails to preserve and turn over such evidence.

Smith said he only found out about the recording, and another one made when Hanson was booked at Troop K, on Nov. 20 as he prepared the case for trial. He said it turned out the dashcam recording was never made.

Hanson is charged with attempted murder, first-degree assault, having an illegal weapon in a vehicle, first-degree robbery, sixth-degree larceny and second-degree criminal mischief. In a separate motion to dismiss, Blanchard has asked the court to dismiss the illegal weapons charge against Hanson because the weapon taken from him was a Columbia River Knife and Tool with a fixed blade less than 4 inches long and is not prohibited under state law.

Judge Barbara Bailey Jongbloed listened to arguments on the motions Wednesday and is expected to rule before the prosecutor begins calling witnesses on Friday.

According to a police report of the incident, state police were called to the Carbery Fields horse farm at 859 Beaumont Highway in Lebanon at 1:22 a.m. on April 28, 2012, for a reported stabbing.

The victim, Shane Crawford, 30, was taken to Windham Hospital, then airlifted to Hartford Hospital, where he underwent emergency surgery.

Hanson had gone to the farm to retrieve items that did not belong to him from his ex-girlfriend, Annie Morris, according to the report. A dispute ensued, and Morris went to a neighbor’s home. Crawford, the neighbor’s boyfriend, went to confront Hanson, who was leaving the farm. Hanson stabbed Crawford multiple times in the back with a serrated knife as Crawford turned to enter the home, according to the report. Crawford was able to get into the house before collapsing. Hanson stayed outside, where he was taken into custody without incident.

Hanson, who has no previous criminal record, claims he stabbed Crawford in self-defense. At the trial, Blanchard is expected to call forensic witnesses who will explain the placement of Crawford’s wounds. In taking the case to a jury, Hanson turned down an offer from the state to plead guilty in exchange for a nine-year prison sentence.

— Karen Florin