HALIFAX -- The jury at the trial of a Halifax man accused of killing a popular yoga instructor was selected Tuesday, as Nicholas Butcher pleaded not guilty to second-degree murder.

Butcher, a 35-year-old graduate of Dalhousie University's law school, is accused of killing 32-year-old Montreal native Kristin Johnston on March 26, 2016.

His trial started Tuesday in Nova Scotia Supreme Court, where dozens of people were called for jury selection.

By day's end, a 16-member jury panel had been chosen -- seven men and nine women.

Justice Joshua Arnold gave the jury brief instructions before dismissing them for the day.

"As the trial proceeds, you may discuss the case among yourselves when all of you are together in your jury room. You must not, however, come to any conclusions about the case during those discussions," said Arnold, who also told jury members not to discuss the case with friends or family.

"Keep an open mind. The time to decide the case is after, not before, you have heard all of the evidence and listened to the lawyers on both sides and my instructions about the law that applies to the evidence."

Arnold told the jury they would hear more lengthy instructions Wednesday morning, followed by the Crown's opening statement.

Butcher, wearing a navy suit with his brown hair buzzed, sat quietly and expressionless next to his lawyers Peter Planetta and Jonathan Hughes during the jury selection process.

Before the jury was selected, Butcher was asked to enter his plea.

"Not guilty," he said, standing at his lawyer's bench.

Outside of court, prosecutor Carla Ball said the Crown will call around 40 witnesses, and will present evidence in chronological order.

Planetta said his client "recognizes the gravity of the situation and the importance of the trial."

Twenty days have been set aside for the trial.

Johnston opened a Bikram yoga studio in downtown Halifax, gaining a reputation as a kind and determined businesswoman with what friends described as a "magnetic" personality.