The case is now closed in the nearly yearlong investigation into the death of a north central Missouri woman.
Sullivan County Sheriff Roger Smiley told KTVO that after interviewing "every possible suspect," the death of
Vickie Anderson, 51, of Boynton has been ruled a suicide.
Anderson's body was found in an outbuilding behind her house on March 28, 2012.
Smiley said the state medical examiner's office determined that the slash wound on Anderson's neck was self-inflicted.
He said the weapon was a thin-bladed knife.
The sheriff said investigators had "no smoking gun" or any other physical evidence to indicate that someone else had killed Anderson.
Smiley admits he was skeptical about the autopsy results.
That is why he kept the investigation going as long as he did before resigning to the fact that the death was self-inflicted.
Over the past 10 months, Smiley said investigators have interviewed several "persons of interest," including the two men who lived with Anderson.
He said both of those men agreed to take a polygraph test, and both men passed the lie-detector test.
Authorities also interviewed family members, friends and neighbors.
Smiley said the autopsy showed Anderson had a blood alcohol content of .218.
No narcotics were found in her system.
Smiley told KTVO he learned during the investigation that Anderson had attempted to take her own life on one or two previous occasions.
Smiley said the case is considered closed unless new information surfaces.
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