In Search of Admissible Evidence

By Tao Yongyan

By using criminal investigation technology as a secret weapon, this person not only makes the deceased"open up" to reveal their grievances, but also is able to trace the real criminals to their hiding places so that they have nowhere to hide. He is the expert who specializes in offering technical support and providing crucial evidence to the investigation and prosecution concerning a large number of major criminal cases.His name is Bai Yongqiang, the deputy director of the Criminal Technology Division of the Criminal Investigation Department in the Yinchuan City Public Security Bureau, Ningxia Hui Autonomous Region.

"Lao (Old) Bai" is not Old

"'Lao Bai' likes to get to the bottom of things.His world is full of question marks!" This is Bai's colleagues' impression of him.

"Lao Bai", as his colleagues usually refer to him,was born in the 1980s. However, because he is a leading expert in DNA technology in the Public Security Bureau, and has been engaged in the field of criminal technology for 12 years long , people prefer to call him the affectionate honorific "Lao Bai".

But few of his colleagues knew that in 2010, when Bai, a competent doctor who had previously practiced clinical medicine for nine years, chose to change his career to become a police officer, he encountered this kind of first "question mark" in his life.

"Only a week ago, I faced patients full of life; but a week later, what I was facing were all cold corpses.This tremendous mental contrast was really a challenge for me!" The memory of his first appearance at the crime scene as a forensic doctor is still fresh to him up to this day. It happened in January 2011, when he had just reported for duty at the Criminal Investigation Department. On that day, he arrived at the crime scene to investigate a fall accident in a high-rise building."In the past, I brought a stethoscope with me wherever I was going, but now I'm carrying a brief case for investigation. In the past, I used to practice traditional Chinese medicine with my professional examining skills such as perceiving, listening, asking, and checking the pulse for my patients, while nowadays my eyes are full of blood stains and mangled bodies. I'm really amazed!"This confusion made the always self-assured Bai doubt about himself. "Can I manage it?"

Bai was affirmative: "Certainly I can!" In the following weeks and months, in the daytime, he would work closely with the experienced forensic doctors and visit crime scenes or conduct autopsies. And at night,he would be absorbed in his old academic textbooks at home to increase his professional knowledge in this area. He also had the habit of examining crime scene photos on file in order to learn more from them. Besides making great efforts to improve his photography skills, he also spent much time enhancing his psychological resilience in tough situations at work. Soon after, "Lao Bai" acquired the credentials to handle cases independently and the authority to issue official medical examination reports. His perseverance and determination in "cracking a hard nut" earned him general approval. Not long after this, he was assigned the job of establishing a DNA testing center in the Yinchuan City Public Security Bureau. With the experience of introducing new equipment to this project and the previous practice of working and learning with his colleagues in the Ministry of Public Security and the Public Security Department, "Lao Bai" gradually obtained a certain level of confidence, albeit occasional doubts from colleagues.

"Is it feasible to rely on a six-month-old laboratory to investigate and solve major criminal cases?"

"There is no room for errors in evidence examination. As to the reliability of this technology,if it fails him because of its deficiency, the negative influence on the result of solving a crime will be irreversible. Can we really count on this young man in his early 30s to do all this?"

To this kind of questioning, his answer was affirmative: "Sure, I can!"

In March 2012, a homicide occurred in Lijinghu Park, Xingqing District, Yinchuan City. After a tremendous amount of effort overnight at the crime scene, Bai eventually extracted from the victim's backpack some key evidence that might have been left by the suspect. But the doubting voice emerged again among his colleagues: "For this minimum amount of trace evidence, there is only one chance to test it. And the result was crucial as to whether the case could be solved successfully. Should we send the evidence back to the Ministry of Public Security for testing, or should we have it tested here in our DNA laboratory?"

"Lao Bai", as the founder of this laboratory, was quite enthusiastic, "Let me give it a try!" He was resourceful in accomplishing this mission. Seeing that the automation level of the equipment was not sufficient for this test, he ran the equipment manually. Realizing that the technology he was relying on was still not fully developed, he chose to stay and keep a watchful eye on the ongoing process. Fearing that any imprecise outcome might occur, he took out all the samples and scrutinized them one by one without exception. In this way, "Lao Bai" stayed in the laboratory for a whole 72 hours. When he at last obtained the matching sample,the whole task force let out a cheer and felt greatly encouraged. With the physical evidence provided by Bai, criminal investigators eventually captured the suspect successfully.

"For me, this is not only a settlement of a case but an encouragement as well. It tells us that, for any future cases with similar characteristics, the Yinchuan Public Security Bureau has obtained the capacity to examine the evidence independently!" This experience still stirs in him strong feelings up to this day.

Making Evidence "Talk"

According to Bai, evidence testing in the DNA testing center turned onto the "highway" after this experiment. Accordingly, he and his forensic colleagues started to get involved in almost all the major thorny criminal cases in the city. To solve those cases, people relied heavily on the physical evidence they provided.In the same period, with the skills and expertise gained from the practice and experience of handling more cases, the laboratory's biological testing technology was becoming more and more mature. As "Lao Bai"recalled, in 2017 alone, he and his team provided technical support for the investigation of more than 4,000 cases in the city and tested more than 22,000 biological specimens. He admitted that the job was very tough for him to handle sometimes. However, whenever a new case came, he would work on it without sleep for days, till the test results came out and were passed over to the investigators and task forces without delay.And then he would take a nap while sitting at his table.But he said he was quite contented and very proud of himself seeing so many cases solved because of his tireless efforts.

As the deputy director in charge of the DNA laboratory, while he was doing a marvelous job in his own post, Bai also made tremendous endeavors to improve the laboratory's management and promote the standardization and perfection of its proceedings and management systems, so that there's no room left for malpractice or testing errors. In 2015, his laboratory took the lead in carrying out a round of DNA testing for the old bones and teeth in the city area that had remained untested for years. This particularly filled the gap in Ningxia province's DNA testing record. He was also active in introducing and localizing many new technologies and technical methods. As a professional instructor with the Department of Public Security, he held many professional and academic seminars inside and outside the autonomous region, which always produced good results.

Meticulous and conscientious in his job, he is also known to be keen on pushing forward the analysis and study of current criminal technologies. Once,in 2019, when he was examining a piece of special physical evidence, he found that the regular reagents and standard methods all failed in the testing. Surprised and confused, he decided to dig deeper into this matter to unveil the potential causes. He began his research and experiment with the help of some similar samples he purchased himself and some of the tools seized by police from Helan and Xixia Public Security Subbranches. After perusing through a large amount of academic literature and resorting to the assistance of college professors to determine the specific compound of the specimen, he eventually located the causes, after still more repeated analysis and research. Later, based upon the knowledge of the causes, he successfully found out the solution to any future problem of this kind. In order to have these breakthroughs, with the support of the "police-enterprise cooperation" model,he worked with a private-owned company and jointly developed a product that could be used to solve similar problems. He even succeeded in applying for a utility patent for it. This is the first patent that Yinchuan Public Security Bureau has acquired in the field of criminal technology in China, again filling the gap in the field of DNA forensic science in Ningxia province.

On January 29, 2020, Bai Yongqiang was analyzing test data in the laboratory when he received an urgent call from the front desk reporting the death of a woman at a bank of the Yellow River in the city's Xingqing District. She sustained several severe head injuries to the extent that her facial features were beyond recognition. His immediate reaction was, "It's likely a homicide and I must get there as soon as possible."When the preliminary investigation was finished, he was certain that it was a murder case. Since the crime scene was located close to the bank of the Yellow River,various kinds of garbage discarded by citizens and even human waste were everywhere. Search areas had to be determined before careful examination could begin.After seven hours of on-site investigation, a total of 110 pieces of physical evidence were recovered, including blood stains, stones, tree branches, toilet paper, cigarette butts, human feces, and several pieces of the victim's clothing.

Bai was certain that certain biological information left by the criminal suspect must be still there among the physical evidence they collected. But to extraction of tiny evidence could involve a large amount of testing,and a very challenging one. He put his full effort into this and worked in the laboratory continuously for 14 hours. When he finally stepped outside, it was already 10 a.m. the next morning. Judging from the testing results of the first batch of evidence, he concluded that part of the data extracted was of great significance. But in the meantime, worrying that any occurrence of errors might mislead the direction of the whole investigation,he decided that he must be certain of every outcome he was working on. After a short break, he entered the laboratory again and started testing with an alternative method. Eight hours later, the testing results for the second batch came in. Three pieces of the data were confirmed to be consistent with each other, making him believe that they were possibly left by the criminal suspect. The task force felt hopeful for this case upon hearing Bai's positive feedback. Soon after this, a man in a suicidal case was found in a county hotel 350 kilometers away from the downtown area, which raised a lot of doubts. Was it related to this on-going case?This question preyed on everyone's mind. Obviously the key to this question was to obtain a positive identification through technical methods. Bai worked overnight on the biological material extracted from the deceased man for testing and comparison. Six hours later, the outcome showed that the two were a definite match. Accordingly, he drew the conclusion that the biological information left on the key physical evidence that was found previously at the scene did come from this man. Combined with the evidence from other relevant investigations, they were certain that this man was the suspect in this case. The suspect had been dead,and naturally, no confession of any kind could come out of him. However, Bai managed to make "the physical evidence talk", and he became the person who could confidently declare that the case was solved.

Find Surges in Quiet Waters

When it comes to criminal technology, "Lao Bai"has a motto: "Find surges in quiet waters!"

Since 2019, according to Bai, with the improvements in the construction of Yinchuan City's social order and the overall social security prevention and control system, the Yinchuan City Public Security Bureau has been establishing its own image around the"Fengqiao" police policy, which places the interests and service of the people in the first place in all aspects. As a result, local police stations have not only achieved significant development and enforcement,but also undergone effective modernization reforms and continuous facility build-ups. And murder cases decreased by nearly 70% among major criminal cases.

Over the years, "Lao Bai" and his young and energetic team gradually shifted their attention from solving major murder cases to pursuing less serious stealing, robbery, and scamming cases, which concern the livelihoods of ordinary people. At the same time,they were active in achieving breakthroughs in terms of child trafficking issues as well as scientific research and innovation in criminal technology. In 2021, "Lao Bai"and his team applied for the approval of an autonomous region-level scientific research project, which was granted for the first time in the field of criminal technology in Ningxia Province.

In 2022, multiple burglary cases occurred in Xingqing District and Jinfeng District. The burglar suspects committed their crimes using specialized unlocking techniques. Though relevant physical evidence can be recovered at the crime scene most of the time, the relevant evidence testing can still be quite a challenge. Once again, Bai resorted to his "secret weapon" specialized in carrying out this type of special evidence testing. After the testing process was carefully finished, he was certain that the valid testing rate by using this method was significantly higher than that from the conventional methods. Besides, this method was extremely convenient to use. Thus, the criminal suspects were quickly identified. What's more, with the help of this case, dozens of other similar cases that occurred from 2018 to 2022 were found to be all committed by the same criminal gang. Later, this testing technology won the National Public Security's Technology Innovation Award for Local Police. With his outstanding performance in solving cases small and major alike, "Lao Bai" relied on advanced technologies and his personal perseverance to make sure that every piece of evidence could "talk" to keep the public safe.