Insanity plea mulled for Connecticut teen in prom stabbing case

Attorney Edward Gavin, Christopher Plaskon's uncle and guardian Paul Healy, Plaskon and attorney...

Attorney Edward Gavin, Christopher Plaskon's uncle and guardian Paul Healy, Plaskon and attorney Richard Meehan, Jr. attend a probable cause hearing in the stabbing death of Maren Sanchez at Connecticut Superior Court in Milford, Connecticut, June 4, 2014. (REUTERS/Arnold Gold/Pool)

Richard Weizel, Reuters

, Last Updated: 2:20 PM ET

MILFORD, Conn. - Lawyers for a Connecticut high school student accused of murdering a female classmate hours before their junior court began talks on Wednesday on whether to amend his plea to not guilty based on insanity or on related grounds.

Christopher Plaskon, 17, pleaded not guilty in June to the fatal stabbing of 16-year-old Maren Sanchez. At a pretrial hearing at Connecticut Superior Court in Milford on Wednesday, his attorney, Richard Meehan, began discussions with Superior Court Judge Frank Iannotti on which variant of the plea to enter.

In addition to a possible plea of not guilty based on insanity, Meehan is considering a plea of not guilty based on not guilty based on extreme emotional disturbance or diminished mental capacity.

"We are reviewing the vast materials and seeking additional evidence," said Meehan, who did not amend his client's plea on Wednesday. The judge said he would take up the matter again on Oct. 16.

Plaskon has been charged with stabbing Sanchez in the chest, neck and face with a kitchen knife in a stairwell at Jonathan Law High School on April 25, the day of the school prom.

Iannotti granted Plaskon's request in June that the case be decided by a three-judge panel rather than a jury.

At Plaskon's May arraignment, Meehan said the teen was exhibiting signs of psychosis, had been on a 24-hour suicide watch and was taking anti-psychotic medication.

Police are still investigating reports the attack came after Sanchez rebuffed Plaskon's invitation to the junior prom.

As he was taken into custody, covered in blood, Plaskon told the arresting officer: "I did it. Just arrest me," according to court documents.