A retired dentist is found not guilty Thursday in the death of a 4-month-old boy, who was poisoned after being given weed killer laced with arsenic at a cookout, instead of water.

Constantine Pitsas, 77, was charged with involuntary manslaughter in the Aug. 9, 2003, fatal poisoning of Benjamin Glynn. and with seriously injuring the boy's 2-year-old sister, Morgan.

After a three-day trial, Judge Patrick Riley delivered the verdict. Pitsas waived his right to have a jury hear the case.

Pitsas did not testify, but told investigators he had bottled water in a refrigerator, which he thought was too cold for the baby. He, instead, for a gallon of what he thought was spring water from the basement.

Assistant District Attorney Gerald Shea said Pitsas, who poured the liquid, ignored or didn't see the warning label attached to the jug handle reading, "arsenical" and "total weed killer."

Pitsas' lawyer, James O'Shea, calls the incident a "tragic accident," with no criminal intent, arguing the label was not conspicuous.

After announcing his verdict, Riley said prosecutors had not proven beyond a reasonable doubt that Pitsas had acted in a "wanton and reckless" manner.

Four-month-old Benjamin drank about six ounces of pesticide, but Morgan had only a couple of sips, complaining it tasted bad. The father says both children became ill within one minute of ingesting the fluid.

When doctors discovered they had swallowed arsenic, authorities organized scrambled to bring in the nearest supply of a rare arsenic antidote, which was 240-miles away at a hospital in Bangor, Maine, where members of a church had been treated four months earlier after drinking arsenic-laced coffee.

The antidote arrived too late to save Benjamin. Morgan spent 13-days in the hospital.