The 74 charges against Mark Goudeau, which also include 15 counts of sexual assault and 11 counts of kidnapping, stem from crimes committed between August 2005 and June 2006 throughout the Phoenix area.
"The reign of terror has ended. The quest for justice has just begun," prosecutor Andrew Thomas said Tuesday.
Defense lawyer Corwin Townsend said Goudeau will plead not guilty to the new charges. He has already pleaded not guilty to two sexual assaults that authorities also attributed to the Baseline Killer.
"We haven't changed our position at all," he said. "The fact that they threw out more charges does not change our belief that they have the wrong guy."
Most of the victims, all but one of them women, were killed going about their daily activities, such as leaving work, washing a car or waiting at a bus stop. The Baseline Killer case originally included eight killings. A ninth was publicly revealed in December.
Police have said the killer usually struck at night and wore disguises, including a wig of dreadlocks and a fisherman's hat. The name Baseline Killer came from the Phoenix street where some of the earliest crimes were committed.
About half of the attacks occurred within three miles (4.8 kilometers) of the home Goudeau shared with his wife. One woman was killed just around the corner.
Police announced last month the man they believed to be the Baseline Killer was in custody and recommended that Goudeau be charged with murder and other crimes. Police said investigators had collected forensic evidence, including DNA and ballistics, implicating Goudeau, reports AP.
Goudeau, an ex-convict, has been in jail since September, when he was arrested in two sexual assaults attributed to the Baseline Killer. Goudeau is still scheduled to face the sexual assault charges in a trial to start Monday. But Townsend said the trial likely will be postponed until March.
Goudeau had previously served 13 1/2 years in prison for three aggravated assaults, armed robbery and kidnapping before being paroled in 2004. He once blamed his history of violence on a weakness for crack cocaine.
On January 15, it was reported that the Russian government began to develop sanctions against several officials at the World Anti-Doping Agency (WADA)