A state prosecutor's insistence that Boston Marathon bomber Dzkokhar Tsarnaev (joh-HAHR' tsahr-NEYE'-ehv) should stand trial a second time has triggered a backlash.

Some people feel it would re-traumatize victims and amount to a waste of taxpayers' money.

Tsarnaev was sentenced to death after being convicted by a federal jury in the bombing, as well as the killing of MIT police Officer Sean Collier three days later.

Middlesex District Attorney Marian Ryan says she still plans to put Tsarnaev on trial for state charges in Collier's death.

Ryan says she believes it's important to prosecute Tsarnaev in state court for Collier's killing as well as the carjacking of a Cambridge man and a firefight with police in Watertown as Tsarnaev and his brother tried to escape.