Baseline Shooter: Mark Goudeau’s Convictions, Appeals, and Civil Suits

Mark Goudeau, known as the Baseline Killer, is an Arizona death-row inmate convicted in 2011 of 67 felonies committed during a 13-month Phoenix crime spree between August 2005 and June 2006, including nine first-degree murders and multiple sexual assaults. A Maricopa County jury sentenced him to death nine times. He remains on death row as of 2026, where his attorneys are pursuing a sweeping post-conviction petition alleging planted evidence, unreliable DNA testing, prosecutorial misconduct, and intellectual disability.¹²

The Crimes Attributed to Goudeau

The spree ran from August 6, 2005, to June 29, 2006, and was prosecuted as 13 separate incidents involving at least 33 victims across the Phoenix area. Eight women and one man were killed. At least five women and three minor girls survived sexual assaults, and several businesses and individuals were robbed at gunpoint.¹²

The “Baseline Killer” nickname came from early attacks on or near Baseline Road in South Phoenix, but the crimes were not confined to that corridor. A significant cluster occurred within a roughly one-square-mile area between Thomas and Indian School Roads and 24th and 32nd Streets, well north of Baseline Road. The attacker typically struck at night and wore disguises, including a fisherman’s hat and a wig of dreadlocks.²³

One of the earliest identified attacks was a double sexual assault on September 20, 2005, when two sisters were raped at gunpoint in a South Phoenix park.⁴ The last known incident came in late June 2006, when surveillance video captured a man snatching a woman from a Central Phoenix carwash; she was found dead a block away.²

The spree ran at the same time as the separate “Serial Shooter” case, in which Dale Hausner and Samuel Dieteman carried out random late-night shootings across the Valley, killing eight people. Phoenix police treated the investigations as unrelated and ran them through separate task forces, with roughly 100 officers assigned to the Baseline Killer case and about 375 to the Serial Shooter case.⁵⁶

Arrest and the Forensic Case

Goudeau was arrested on September 6, 2006, initially in connection with the September 2005 double rape of the two sisters. He was found in possession of drugs at the time of his arrest. He was already in custody on 20 counts tied to those sexual assaults when, on December 8, 2006, police announced that DNA, ballistics, and other evidence linked him to all nine Baseline Killer murders and recommended 71 additional counts.³²

The forensic case rested on two main pillars. The first was DNA. According to prosecutors, Goudeau tried to defeat DNA collection by forcing victims to spit into his hand and then rubbing the saliva onto parts of their bodies he had touched, creating what investigators called a “genetic soup.” Standard testing could not produce a complete profile from the mixed samples, so the Arizona Department of Public Safety lab used an experimental Y-chromosome (Y-STR) test capable of isolating male genetic material. DNA from two murder victims was also identified on items seized from Goudeau’s home, and his DNA was found on a murder victim and several sexual assault survivors.²⁷

The second pillar was ballistics. The murder weapon was never recovered, but the prosecution’s expert testified that toolmark analysis of bullets and shell casings showed a single .380 caliber handgun had been used in all nine murders and in the other charged crimes where casings were found. Investigators also recovered a ring belonging to one of the murder victims hidden inside a shoe at Goudeau’s residence.⁷

Trials, Convictions, and Nine Death Sentences

Goudeau went to trial twice. The first case, covering the September 2005 double sexual assault, ended in September 2007 with convictions on 19 counts of sexual assault, sexual abuse, kidnapping, and aggravated assault. He received 438 years in the Arizona Department of Corrections for those offenses alone.⁴

The larger murder trial followed. A Maricopa County grand jury indicted Goudeau on January 16, 2007, on 74 felony counts, including nine counts of first-degree murder, multiple sexual offenses against adults and minors, aggravated assaults, kidnappings, and twelve armed robberies. Two counts were dropped before the case went to the jury. Prosecutors presented the evidence in “13 chapters,” one for each attack, in chronological order.⁸²

Goudeau pleaded not guilty. His defense argued there were “likelier suspects” and worked to discredit the Y-STR DNA testing and other physical evidence linking him to the scenes. The defense also moved to sever the 74 charges into separate trials, arguing that one trial covering 13 incidents risked overwhelming the jury. Judge Warren Granville denied that motion and a motion to suppress evidence seized from Goudeau’s home.⁹¹⁰

On October 31, 2011, the jury convicted Goudeau of 67 felony charges, including all nine counts of first-degree murder. He was acquitted on one count of armed robbery, two counts of attempted armed robbery, and one count of kidnapping. The jury could not reach a verdict on one count of sexual abuse. On November 30, 2011, the same jury returned death sentences for each of the nine murders, which Judge Granville entered.¹

The 2016 Arizona Supreme Court Ruling

Nine death sentences triggered an automatic direct appeal to the Arizona Supreme Court. Goudeau’s attorneys argued the charges should have been tried separately and that the destruction of DNA samples during testing violated his due process and Sixth Amendment rights by denying the defense a chance to observe or independently analyze the evidence.¹¹¹⁰

In 2016, the court upheld all 67 convictions and the nine death sentences. It found no abuse of discretion in the trial court’s refusal to sever the charges, held that consumption of DNA evidence did not violate Goudeau’s rights absent bad faith by the state, and rejected claims of prosecutorial misconduct and ineffective assistance of counsel.¹²²

The 2026 Post-Conviction Petition

In February 2026, Goudeau’s current attorney, California-based lawyer John Mills, filed a 384-page petition for post-conviction relief in Maricopa County Superior Court. The petition asks the court to vacate all convictions and sentences and seeks a new trial, Goudeau’s release, or commutation of the death sentences to life imprisonment.²

The petition raises several categories of claims. It alleges that Phoenix police purchased a duplicate ring at Walmart and planted it in Goudeau’s closet, and that officers applied autopsy blood to a ski mask and shoes found in his home to fabricate forensic links to the murders. It argues the Y-STR DNA test used at trial was inconclusive because it could not produce a unique genetic fingerprint and could have matched any of Goudeau’s male relatives. It accuses prosecutors Suzanne Cohen and Patricia Stevens of allowing witnesses to give “demonstrably false” testimony and ignoring police corruption. It contends trial counsel failed to use phone records to establish alibis, failed to challenge ballistics and eyewitness identification, failed to present evidence of alternative suspects such as gang members and ex-partners of victims, and failed to adequately inform the jury during the penalty phase that Goudeau would face natural life in prison even without a death sentence because Arizona abolished parole for most crimes in 1993.²

Finally, citing Atkins v. Virginia (2002), which bars execution of intellectually disabled defendants, the petition argues Goudeau has “borderline intellectual functioning and severe verbal deficits,” pointing to a 1990 presentence report that noted a reading level below sixth grade. Mills told the Arizona Mirror that Goudeau himself is more focused on the misconduct allegations: “I know that Mark would not want an Atkins claim emphasized. What he cares about is the misconduct in the case and his innocence.” Corwin Townsend, the lead defense attorney at Goudeau’s original rape trial, said the disability argument “never crossed my mind” and described Goudeau as a “complete participant” in his case and in the “upper echelon of defendants I’ve had.”²

As of April 2026, the Arizona Attorney General’s Office had not responded to the petition and declined to comment publicly. The proceedings are expected to involve extended litigation. Goudeau, now 61, remains on death row.²

Civil Suits by Victims’ Families

Families of two murder victims sued the City of Phoenix, arguing that police failures in processing DNA evidence from the September 2005 double rape allowed Goudeau to remain free long enough to kill their relatives. Alvin Hogue, husband of victim Romelia Vargas, and Maria Nunez, sister of victim Sophia Nunez, alleged that the Phoenix Police crime lab held two DNA swabs from the 2005 assault in storage rather than testing them promptly, and that prompt use of available Y-STR technology or submission to the state lab could have identified Goudeau sooner.⁴

The suits were dismissed. In 2014, Maricopa County Superior Court Judge Arthur Anderson ruled that holding the city liable for failing to identify an unknown suspect would create “insurer-like liability” for law enforcement. In July 2016, a three-judge panel of the Arizona Court of Appeals affirmed, finding that the city had no “special relationship” with the victims and had not undertaken to provide specific protection against Goudeau, and was therefore shielded by Arizona’s governmental immunity statutes.¹³

1
Maricopa County Attorney’s Office. Baseline Killer Sentencing
2
Arizona Mirror. Was There Really a Baseline Killer
3
Police1. Phoenix Police Link Man to 9 Baseline Killer Murders, 2 Assaults
4
Courthouse News Service. Families Blame Phoenix Police for Letting Baseline Killer Suspect Slip
5
USA Today. Summer of Fear: Killers Terrorized Phoenix in 2006
6
Rutland Herald. Phoenix Police Arrest 2 Alleged Serial Shooters
7
Arizona Supreme Court. State v. Goudeau Opinion
8
Maricopa County Attorney’s Office. Baseline Killer Sentencing
9
CBS News. Defense to Give Closing Arguments in Baseline Killer Trial
10
FindLaw. State v. Goudeau
11
Arizona Republic. Baseline Killer Mark Goudeau Arizona Supreme Court
12
Tucson.com. Death Sentences of Phoenix’s Baseline Killer Are Upheld
13
Courthouse News Service. Phoenix Immune From Baseline Killer Suits