Christensen became obsessed with serial killers in the months before for he kidnapped Zhang, Miller said, adding that Christensen was engrossed by the novel "American Psycho" and was intent on slaying someone in order to fulfill a goal of infamy that he'd set for himself.
Brendt Christensen, 29, could face the death penalty if he is convicted in the June 2017 abduction and murder of Yingying Zhang, a 26-year-old student at the University of IL at Urbana-Champaign, 130 miles (210 km) south of Chicago.
After opening remarks, federal prosecutors will call their first witnesses.
The case is being closely watched by Chinese students across the U.S. The University of IL has more than 5,000 Chinese students, among the largest such enrollments in the nation.
On the day of the murder, Christensen was driving around looking for a victim when he found Zhang, a student of small stature and with limited English, Miller said.
The defense attorneys for a former University of IL doctoral student admitted to the jury Wednesday that their client brutally beat and killed a foreign exchange student from China, but stressed that he "is on trial for his life", in a case that could warrant the death penalty.
Christensen's defence lawyer acknowledged in his opening statement that his client killed Zhang but disputed the prosecution's version of events.
"Her blood ran down the wall", Miller said, as Zhang's relatives listened to an interpreter through headsets. He then decapitated her and disposed of her body, which has never been found. The jurors were picked Tuesday after a jury-selection process that lasted more than a week. Zhang, petite at 5-foot-4, tried to fight back but Christensen proceeded to choke her.
The federal death-penalty case is the first in IL since the state struck capital punishment from its books on grounds death-penalty processes were too error-prone.
"Brendt Christensen killed Yingying Zhang", Taseff went on.
Zhang's parents traveled to the USA from China to assist in the search for their daughter after her disappearance in 2017 and have returned to IL along with Zhang's boyfriend for the trial. He later pleaded not guilty to kidnapping resulting in death.
While the defense agreed Christensen kidnapped and killed Zhang, Tesseff said they took issue with prosecutors' explanation of "how and why". Tesseff portrayed Christensen's life as being in turmoil leading up to Zhang's disappearance, saying marital and drinking problems only made matters worse. In his first few semesters as a doctoral student, Christensen was making straight As but by late 2016 was getting Fs in all his classes. They will raise Christensen's mental health, and call into question some of the things Christensen is heard saying on Federal Bureau of Investigation recordings.
Miller said the informant, Christensen's then-girlfriend, recorded multiple conversations between herself and the defendant. The government confirmed for the first time that there is DNA evidence linking Christensen to the crime.
Christensen was arrested on June 30, 2017, his birthday, after his girlfriend wore a wire for the Federal Bureau of Investigation in a bid to capture incriminating statements by Christensen. The girlfriend is expected to be the government's star witness.
Prosecutors will have to prove that Zhang is dead in the absence of a body, but mounting evidence, including from a cadaver-sniffing dog used by authorities in Christensen's apartment, indicates that a dead body had been there. Prosecutors described, in great detail, Christensen's alleged admission of what he had done to Zhang on these recordings.
Zhang's parents, her brother and boyfriend are in IL for the trial.