LEWISTON — The trial of Diane Silsby, blamed for a July 2009 car crash that killed a Lewiston mother, has been put off again.

Silsby, of Lunenburg, Vt., was scheduled to stand trial this month at Coos County Superior Court in Lancaster, N.H., on three counts of negligent homicide. The trial was postponed to Jan. 18.

Rachel Metivier, 26, of Lewiston and two other people — Silsby’s 83-year-old mother, Leona Dunn, of Lancaster, N.H., formerly of Waterford, and her 15-year-old daughter, Nicole — were killed in the head-on crash that took place on Route 2 in Randolph, N.H.

Police say Silsby was under the influence of alcohol at the time of the accident.

The accident, which occurred July 3, 2009, also injured four people. Silsby was taken to Dartmouth Hitchcock Medical Center after the crash. Four months later, she was indicted on the homicide charges. Last December, she entered a not guilty plea.