The penalty phase begins Wednesday in the Samuel Dieteman murder case in Phoenix.

Dieteman faces a possible death penalty after pleading guilty to two murders in metro Phoenix's Serial Shooter attacks in 2005 and 2006.

Dieteman was the key witness against co-defendant Dale Hausner, who was sentenced earlier this year to death for the random 14-month shooting spree that left six people dead and 19 others injured.

Dieteman is hoping jurors will spare his life for his cooperation with investigators.

Opening arguments at Dieteman's sentencing trial are set for Wednesday. If jurors decide against giving him the death penalty, Dieteman is guaranteed a life sentence.

• Condemned Ariz. serial killer gets 2 life terms
  Condemned Ariz. serial killer gets 2 life terms

  A man convicted of killing six people and attacking 19 others was sentenced to two consecutive life terms plus nearly 365 years on Monday, just days after being condemned for the dozens of random...

  Read Full Story »
• Jury considers penalty in Ariz Serial Shooter case
  Jury considers penalty in Ariz Serial Shooter case

  Jurors who convicted a former janitor of murdering six people and attacking 19 others will begin work Monday to decide whether he should be put to death for the dozens of random, nighttime...

  Read Full Story »
• Arizona court hears 'Serial Shooter' death-penalty appeal
  Arizona court hears 'Serial Shooter' death-penalty appeal

  The Arizona Supreme Court heard arguments Tuesday in the appeal of convicted "Serial Shooter" Dale Hausner, who was sentenced to death six times in March 2009.

  Read Full Story »
• Serial Shooter jury begins considering sentence
  Serial Shooter jury begins considering sentence

  Jurors have returned to a Phoenix courtroom to begin deciding on life or death for the man convicted in a series of random nighttime shootings that terrorized the city. Dale Shawn Hausner was...

  Read Full Story »
• Dale Hausner -- 'Serial Shooter' guilty of killing six
  

  Dale Hausner -- 'Serial Shooter' guilty of killing six

  Dale Hausner , known as one of the "Serial Shooters" was found guilty of six out of eight murder...

  Read Full Story »