In March of 1998, within the span of 72 hours, two city officials and a local family in the city of Fremont, California, were the victims of fire-bomb and pipe bomb attacks. Four devices exploded and another two were discovered and disposed of by the city’s bomb squad. While no one was injured, the bombings caused a sense of panic in the community. With detectives at a loss to find any pattern linking the targets, local officials called in the federal bureau of Alcohol, Tobacco, and Firearms (ATF) to analyze the bombs. However, according to Alameda County deputy district attorney Tom Rogers, “The electronic aspects of the devices were beyond the expertise of anyone at the ATF…. [the devices were] the largest as well as the most electronically sophisticated domestic pipe bombs the ATF had ever encountered.” Out of the usual options, Rogers turned to Brian Andresen, head of the Forensic Science Center (FSC) at Lawrence Livermore National Laboratory.
Brian Andresen came to LLNL in 1983, working as a self-described “analytical chemist” on a variety of projects for the Biomedical and Environmental Sciences divisions. Before joining the Lab, Andresen had worked as an associate professor in the Department of Pharmacology at the Ohio State University College of Medicine. There he and others were among the first scientists in the world to use chemical identification methods on amniotic fluid samples to check the health of in vitro babies. In 1991, Andresen became the founding director of LLNL’s Forensic Science Center. Like many of his colleagues, Andresen’s background was varied and included work in forensics, chemistry and — fortunately in the Fremont case — electronic circuitry.
For the Fremont investigation, Andresen began by piecing together the bomb fragments, searching for chemical and physical clues that might identify the bomber. According to Andresen, he was “brought in to retro-engineer the electronics of the timing circuit and to discover how they worked.” What he found amazed him. While the basics of the bomb were straightforward, the timing circuit was not. The unique system, consisting of a digital watch attached to a small relay circuit, allowed for the bomb to be set months in advance. In addition to this set-up, the bomber used modified car sparkplugs as detonators in the other explosive devices. “It was a very elegant approach,” Andresen said. “The design of these devices showed on-the-edge sophistication.”
While Andresen was able to provide an understanding of how the bombs worked, the police were still no closer to identifying a suspect. However, fortune intervened. While doing a neighborhood canvas, detectives noted a man who overreacted to basic questions with claims of police persecution. Upon bringing the man in for additional questioning, fortune struck again when an inmate in jail on an unrelated matter told police that this individual may be the Fremont bomber. He related that the suspect had paid him $20 to rent a storage locker under his own name. With warrant in-hand, the detectives opened the locker and discovered more electronic circuit boards, gunpowder, books on how to make bombs, chemicals used to make explosives and thousands of pages of documents. The man in custody was Rodney Blach, a former Chicago Police Department forensic investigator.
However, despite the fortuitous finding, the evidence in the locker was circumstantial, and the prosecution needed to link the discovered materials to the bombs used in the attacks. Fremont officials again turned to Andresen. The Lab’s FSC head began by studying the new circuit boards, comparing the wiring and soldering techniques with the boards used in the bombings. Despite the sophistication of the design, Andresen found that the boards were clearly homemade. In particular, he noted that the bomb circuit board had been inexpertly soldered on the wrong side — a finding that was important to linking the pipe bombs to Blach.
For the district attorney, resolving how a sparkplug was adapted to serve as a detonator turned out to be key to overcoming the defense’s argument that a sparkplug could not conduct the detonating electrical signal in the configuration laid out by the prosecution. However, Andresen was able to show that it could. He made working prototypes of all the timer circuit boards and sparkplug components for courtroom testimony.
According to district attorney Rogers, “If we did not have Brian Andresen’s expertise, there would have been a giant hole in our case…. Neither the ATF nor the FBI had any expertise in electronic circuitry. His work and expertise were invaluable to our successful prosecution.”
In 2001, Rodney Blach was sentenced to 37 years in prison.
Brian Andresen continued to serve as head of the Lab’s Forensic Science Center until 2002, retiring not long after. Throughout his career, Andresen and his FSC colleagues worked diligently to primarily provide support to U.S. nonproliferation and counterterrorism programs, while still assisting federal and local law enforcement in a variety of medical and criminal investigations.
Today, LLNL’s FSC continues to serve as home to nationally recognized scientists and capabilities that support chemical, explosive, nuclear and biological counterterrorism — delivering critical assessments and technologies to homeland security, intelligence communities, law enforcement and health professionals.