SANFORD (CBSMiami/AP) – For a third day, attorneys tried to seat a jury for the trial of George Zimmerman, the man charged in the shooting of an unarmed Miami teen.

Attorneys stopped questioning a juror in his 20s, known as “R-39” because potential panelists can be identified only by their numbers, when he said that “murder is murder,” even if it’s self-defense.

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Zimmerman, 29, is pleading not guilty to second-degree murder, claiming he shot17-year-old Trayvon Martin last year in self-defense.

The potential juror left the Florida courtroom without defense attorneys asking questions.

Attorneys had interviewed 18 potential jurors by lunch break Wednesday on the third day of selection. By the end of the day Tuesday, more than 70 jury candidates had been dismissed.

The four potential jurors questioned Wednesday morning also included a white woman in her mid-20s who expressed concerns about her safety if picked; a black woman in her 20s who lived nearby the shooting but said she hadn’t formed an opinion about it; and a white woman in her 50s who didn’t like the negative image of Sanford that was portrayed in the media after the shooting happened there.

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In the jury selection process established by Circuit Judge Debra Nelson, once 30 jurors have been questioned individually about pretrial exposure and have not been dismissed for cause or hardships, they will be brought together as a group for broader questioning by lawyers on both sides. Thus far, Zimmerman’s attorneys have been unable to find potential jurors who hadn’t heard something about the fatal shooting of Martin.

A 44-day delay in Zimmerman’s arrest led to protests around the U.S. They questioned whether the Sanford Police Department was seriously investigating the case of Martin, a black teen from the Miami area. Zimmerman, who was a neighborhood watch volunteer in his gated community of Sanford, identifies himself as Hispanic.

Nelson has said she will keep the identities of the selected jurors anonymous but she rejected a defense request to sequester the initial jury pool of 500 residents.

Attorneys need to find six jurors and four alternates. In Florida, 12 jurors are required only for criminal trials involving capital cases, when the death penalty is being considered.

Defense attorneys have asked potential jurors if being isolated during the trial would be a hardship, indicating they plan to ask Nelson to sequester the jury. Jury candidates who move on from the initial round of questioning about their knowledge of the case, face other rounds of interviews with the attorneys.

By the end of Tuesday, the attorneys had questioned 14 potential jurors in person, and 70 jury candidates had been dismissed after filling out an initial questionnaire. That includes 30 released Tuesday.

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