Waltham Teen Pleads Guilty to Conspiracy, Weapons Charges, For Planning Fatal Robbery Attempt

A Waltham man pleaded guilty today to charges in connection with his role in a failed robbery plot last year that led to the death of a Waltham teenager, said Middlesex District Attorney Marian Ryan.

Steven Tran, 18, pleaded guilty to charges of conspiracy to commit armed robbery and possession of an electrical weapon. He was sentenced by Middlesex Superior Court Judge Kathe Tuttman to 3 to 4 years in state prison on the conspiracy charge, with an additional three years of probation on the weapons charge, to be served after his release from prison.

“It was clear from evidence gathered that Steven Tran expected trouble when he arranged the meeting,” said District Attorney Ryan. “Clearly, he brought friends with him and clearly he brought a weapon because he was planning to commit a crime.”

Waltham Police Chief Keith MacPherson added, “I am pleased to see that justice was served regarding defendant Steven Tran and I look forward to moving ahead regarding the cases of the other defendants.”

Authorities said that Tran arranged to meet Taylor Poulin, 22, of Waltham on March 20, 2014 at the Gardencrest Apartments, 20 Middlesex Circle, in Waltham under the pretense that he was arranging the purchase of two pounds of marijuana. Tran arrived with a hand-held stun gun, had no money, and was withTyler Zanco, a 17-year-old high school student, and a third man who was also a minor.

When Poulin arrived with the marijuana, said authorities, he brought with him Domingo Mendes, 23, of Belmont, and a loaded handgun.

A fight broke out when Zanco attempted to rob Poulin with Tran’s stun gun.

Poulin is alleged to have struck Zanco in the head with a handgun during the altercation, and when Zanco fled on foot, authorities allege that Mendes used Poulin’s gun to shoot Zanco in the back, said the press release.

Zanco was rushed to Newton-Wellesley Hospital, where he was pronounced dead.

Mendes and Poulin were arrested after the incident and face multiple indictments in Middlesex Superior Court.

Mendes is charged with murder, carrying a firearm, conspiracy to commit armed robbery, and commission of a felony, conspiracy to commit armed robbery, conspiracy to distribute a Class D substance, attempt to commit a crime, possession of a firearm, possession with intent to distribute a Class D substance, and a park zone drug law violation.

The cases involving Mendes and Poulin are scheduled for trial Aug. 10, 2015.

These charges are allegations and the defendants are presumed innocent until proven guilty.

The prosecutor assigned to this case is Assistant District Attorney David Solet. The Victim Witness Advocate is Anne Foley.