As many as 24 people were being eyed in the summer of 2006 as potential suspects in the Serial Shooter killing spree until a secret informant led police to zero in on two men in Mesa.
That informant, since identified as Ron Horton, called police tip lines three times in July 2006 telling investigators that they should be looking at a man named “Sammy” for the killings.
In the first two calls, Horton kept his own name out of the messages. He also failed to provide a last name for Sammy.
But in the third call on July 25, Horton spilled everything he knew. The suspect’s name was Sam Dieteman, and he left his own name so he could be contacted.
It was a major break in the series of dozens of random shootings that had put the Valley on edge that year.
During testimony Wednesday in Maricopa County Superior Court in the trial against Dale Hausner, Phoenix police detective Clark Schwartzkopf told how he and the other investigators came across Dieteman and Hausner as the main suspects in the Serial Shooter case.
Before Horton first called the Silent Witness tip line on July 16, investigators were having little luck figuring out who was behind the series of killings and other attacks that already left seven people dead.
In fact, Schwartzkopf testified, police had to deal with the fact that another serial killer, known as the Baseline Killer, also was terrorizing the Valley at the time.
The two simultaneous serial killer investigations were often getting confused by citizens and police alike.
“There were a lot of mix-ups between task forces,” Schwartzkopf said. “A lot of the confusion was because of the number of tips. At one period in mid-July, there were 2,000 tips that came in a two-day period.”
Many of the tips also were bogus or unreliable.
“I had one person call and say they thought it was the Zodiac Killer, the infamous Bay Area serial killer,” Schwartzkopf said. “I had psychics. I had people with crystal balls. I had all kinds of people calling in to tell me who they thought it was.”
Schwartzkopf said investigators even went as far as to record and investigate the license plates of every person who attended town hall meetings set up to tell the public about the shootings, but that did nothing to help.
During the weeks of investigation, the police eventually came up with 24 people who were “persons of interest” or potential suspects, but none became solid leads.
Horton’s tip was the only thing that proved reliable.
When Schwartzkopf was able to finally contact and meet with Horton in late July, he convinced the Phoenix man to set up a meeting with Dieteman.
During the Aug. 1 meeting at the Stardust Lounge in Glendale, undercover officers watched as Horton and Dieteman talked. Eventually, a silver-blue Toyota Corolla pulled up outside that matched the description of a car investigators were looking for in connection with the killings.
Police ran the license plate through their computers. It was registered to Hausner.
After that, the investigators quickly honed their attentions to the two men who were living at an apartment in west Mesa.
They placed a GPS tracking device on Hausner’s car one day when he stopped briefly at the Metrocenter mall in Phoenix.
They also constantly tailed the two men and convinced Maricopa County Attorney Andrew Thomas to authorize secret recording devices to be placed in the men’s apartment and car.
Prosecutors are expected to get into more details of the GPS tracking, as well as play hours of the secret recordings during the Hausner trial on Monday.
Dieteman himself has agreed to testify and may do so soon. He has already pleaded guilty to two of the murders in the killing spree and agreed to be a witness for the prosecution.
Dieteman, considered the star witness , may take the stand as early as next week, but the chances of that look increasingly slim as recent testimony has taken longer than expected.
If prosecutors don’t call Dieteman next week, they will likely wait until the new year to do so.
Horton, the key tipster, will not be testifying. He died earlier this year after complications from an infection.