BANGOR, Maine — A South Windham man, who has successfully used an insanity defense before, filed an insanity defense notice at U.S. District Court in Bangor on Friday for a criminal case in which he is charged with sending cyanide to a suicidal man in England.
Sidney P. Kilmartin, 52, was indicted by a federal grand jury in November on one count each of mailing injurious articles and mailing injurious articles that resulted in death. He entered a not guilty plea in November to the charges against him.
Kilmartin allegedly advertised the drug online as “a painless and quick way to commit suicide” and offered to sell “industrial grade” potassium cyanide for $250 per gram, according to federal documents unsealed at the end of March in the U.S. District Court in Bangor.
According to the indictment, Kilmartin caused the death of Andrew Denton of Hull, England, when he mailed potassium cyanide to him once in November 2012 and again the following month.
Denton’s body was found on Dec. 31, 2012 at his home by a relative and his death was ruled a suicide. In 2013, English police launched an investigation into how Denton, 49, who suffered from depression and had made previous suicide attempts, obtained the potassium cyanide found in his system.
Emails and letters connected Denton to Kilmartin.
Potassium cyanide is a highly toxic chemical asphyxiant that can be rapidly fatal, according to the U.S. Centers for Disease Control and Prevention. It typically is used for fumigation, electroplating and extracting gold and silver from ores.
Kilmartin, who has been in custody since his arrest on Nov. 5, 2014, was found not criminally responsible on Sept. 9, 2009, for crimes he committed in 2007, including the aggravated assault of an elderly man, and was committed to Riverview Psychiatric Center in Augusta, according to a previously published report.
Kilmartin was in the custody of the Department of Health and Human Services when he allegedly sent the poison to England but living in the community, rather than at Riverview. At Kilmartin’s bail hearing on Dec. 8, Kilmartin’s attorney, James Billings of Augusta, told U.S. Magistrate Judge John Nivison that Riverview had refused to house Kilmartin while he awaited trial on the federal charges.
If convicted, Kilmartin faces up to life in federal prison. The U.S. attorney’s office in Maine is not seeking the death penalty, according to court documents.
BDN writers Judy Harrison and Beth Brogan contributed to this report.