article_snippet: MIT police officer Sean Collier, 27, was found gurgling and covered in blood April 18, 2013 after prosecutors say he was shot in the head and neck by Dzhokhar Tsarnaev or
article_snippet: A recording of that radio call was played to jurors hearing the trial of accused bomber Dzhokhar Tsarnaev, 21, on Wednesday, as prosecutors turned to the charge that the defendant and his older brother murdered MIT police officer Sean Collier on April 18, 2013, in an unsuccessful attempt to steal his .
article_snippet: I could hear gargling coming from Sean Collier mouth,' Henniger testified at U.S. District Court in Boston, where the jury hearing Tsarnaev's trial will also decide whether to sentence Sean Collier to death if Sean Collier is convicted of killing three people and injuring 264 with a pair of homemade bombs at the April 15, 2013, race.
article_snippet: Tsarnaev's attorney says Dzhohkar's brother Tamerlan was the mastermind of the bombing and the one who pulled the trigger to kill Sean Collier.
article_snippet: Prosecutors say the mastermind of the bombing and the one who pulled the trigger to kill Collier were culpable in the officer's murder and that the mastermind of the bombing and the one who pulled the trigger to kill Collier killed the 27-year-old in order to steal his gun and arm Tsarnaev .
article_snippet: Prosecutor William Weinreb said in Prosecutor William Weinreb opening statement last week that Prosecutor William Weinreb was unclear if Tsarnaev or Tsarnaev brother fired the weapon that killed Sean Collier but argued that both brothers were equally culpable in the officer's death.
highlights_snippet: Prosecutors say Dzhokhar Tsarnaev or Dzhokhar Tsarnaev brother killed MIT officer Sean Collier, 27, days after the bombing in a failed attempt to steal Dzhokhar Tsarnaev gun .
  