1. "Sawmill" murder case.
After Pan Am flight attendant Kelly disappeared, her husband was considered the biggest suspect, but the man passed polygraph tests three times. But reports later emerged that the victim's husband was seen hauling a large sawmill down the street that night and that he had rented a meat grinder for the day.
In the cold winter, Li Changyu tried to melt more than two feet of snow to find evidence. He placed a frozen dead pig on a branch and stuffed it into a wood chipper for a reduction experiment. In the end, he found 56 broken bones, 2,660 hairs, 3 ounces of flesh and one tooth. The total weight of these evidences was only 365,438+0 grams, but the victim's DNA was accurately detected.
Subsequently, the police found an old electric saw. Li Changyu used scientific methods to display the number of the electric saw, and finally found out that the murderer was the husband of the deceased.
2. Half a fingerprint solved the problem for 30 years.
One day at noon, an 18-year-old girl went to the indoor parking lot of a shopping mall. Her car was parked on the seventh floor, but her body was found on the stairs to the ninth floor. A knife penetrated his left chest and pierced his heart. The girl's clothes and pants were neat and there were no signs of sexual assault, but her shoes and wallet were missing. A handkerchief was found next to the car, and an examination revealed no results.
This case has become unsolved. For more than ten years, the deceased's father has not given up his efforts to catch the murderer. He has sold all his belongings out of necessity. In desperation, he found Li Changyu.
Through photos from the scene, Li Changyu found bloody fingerprints on the tissue box behind the car. They found the tissue box, but the person handling the evidence used the wrong drug and left no clues. With the mentality of giving it a try, Li Changyu used chemicals and lasers again. As time goes by, he finally found half a fingerprint. However, when they searched in the fingerprint files, there was no matching information. It was obvious that the killer had no previous criminal record.
The case remained unsolved until the death of the deceased's father. Li Changyu's team never gave up on the case. Two years later, a woman came into police sight. The results of the fingerprint comparison cannot convict her because there are various possibilities for her fingerprints to be left on the tissue box. For example, she wanted to buy this box of tissues, and her fingerprints happened to be left on it.
So, Li Changyu focused on the handkerchief left at the scene. Because after many tests, the handkerchief was riddled with holes, but they found a bit of snot on it. Snus is often a detail that many chemists overlook. Fortunately, Li Changyu found DNA in the nasal mucus and confirmed that it belonged to that woman.
Skynet is restored, the 30-year-old unsolved case is finally solved, the murderer is sentenced to life imprisonment, and the deceased and her father can finally close their eyes.
Simpson is suspected of killing his wife.
In 1994, the case of former American football player Simpson murdering his wife became the most sensational incident in the United States at that time, not only because Simpson was a well-known star in sports, movies, and advertising, but also because of the dramatic development of the case. During the hunt for Simpson in June 2017, the three major television networks in the United States stopped broadcasting all programs at the same time, and all focus was on the entire process of Simpson being hunted by the police.
On June 12, police discovered that Simpson’s white ex-wife Nicole and her white boyfriend had been assassinated in front of her home. The first murder suspect identified by police was Nicole's ex-husband Simpson. The police found blood stains with the same blood type as Simpson's at the crime scene. Later, they found blood stains during a search of Simpson's residence and found physical evidence such as gloves and sneakers that were consistent with the traces left at the accident scene.
Everything seemed to be solid evidence, but Li Changyu saw the flaw. At 10:30 p.m., Simpson was on the phone. At 11 o'clock, his car came to pick him up at the airport. The whole case was committed in just 30 minutes. In such a short period of time, you have to kill two people with a knife, rush from the first scene to the second scene, jump into the wall to take off your gloves, then go upstairs to take a shower, destroy all evidence, and finally get in the car and rush to the airport. This is even more magical than the plot of the movie.
From the first day of the investigation, Li Changyu believed that the murderer should be two people, and the bloody shoe prints found at the scene were also confirmed to be two types. However, the police identified Simpson from the beginning and announced the results. In an irreversible situation, the police need to collect sufficient evidence.
Through DNA identification, some evidence was found related to Simpson, but Li Changyu also found that there were preservatives in the blood of the DNA, and there could be no preservatives in the blood flowing out of the human body. Plus, Simpson can't wear that bloody glove.
Some people say that these are leather gloves that have shrunk because there is blood on the outside, but there is very little blood on the gloves. What's more, the wall is 3 meters high, and even Jordan can't jump over it. If he climbed over, the creepers growing on the wall would definitely cut the murderer, but there were no such marks.
The so-called evidence of the police is untenable. The case trial at that time lasted 13 months, and the jury finally acquitted Simpson, leaving only the civil court to rule responsible for the deaths of the two people.
4. The situation of three generations of grandparents.
There is a family of three in Connecticut. The grandmother, who is in her 70s, lives in isolation. Her son was born deaf and blind, and her little granddaughter was only seven years old. On a stormy Friday night, three generations of grandparents were killed. The old lady was stabbed more than 30 times, her son was stabbed more than 20 times, and her granddaughter was stabbed 17 times. Rivers of blood flowed.
This is the most impressive case of Li Changyu. The scene was horrific. He and his colleagues first analyzed the murderer's motives. The family has no money, no enemies, and no drugs, so what caused them to fail?
At first, the police believed that the old lady’s daughter and son-in-law did it to seize the inheritance. But Li Changyu found a watch at the scene. After returning, Li Changyu found a hair on the watch, which was found to contain black skin tissue. At the same time, Li Changyu and his colleagues found a large handprint at the scene, which looked like the hand of a black basketball player.
After investigation, Li Changyu’s team discovered that the assistant basketball coach of a middle school in the area was black. He was the captain of the school's basketball team. He took all the scholarship money and went to the West to play, but later returned to this small town because of drug abuse.
After identifying the suspect, Li Changyu and his colleagues found another shoe print and a matching shoe nearby. DNA was found in the shoe, and the black basketball assistant was eventually arrested. By law. It turned out that he wanted to borrow the phone that day, but later he found that the old lady was alone at home, and he had the evil idea of ??murdering her life for money.
5. JFK Jr. Rape Case.
In the United States, sex cases are not surprising, but they have attracted much attention because of famous suspects, such as basketball superstar Kobe Bryant, former US President Clinton, and JFK.
In 1991, dancer Patricia Bowman caused an uproar when she sued Smith Kennedy for rape. JFK Jr. has always been a fancy name. Whether it was rape or consensual behavior became the key to the case.
According to Patricia's confession, she and Kennedy met in a bar that night. They then walked on the beach and kissed. Suddenly Kennedy Jr. wanted to have sex with her, but the woman refused. Patricia tried to escape but struggled for the latter for five minutes. Patricia broke away and fled to the backyard. Kennedy Jr. caught up with her and raped her on the lawn for twenty or thirty minutes.
In Li Changyu’s eyes, this is a case with no technical content.
First, according to the testimony, Patricia struggled on the ground for five minutes and must have had bruises, abrasions on her skin or torn clothing. But when the doctor checked the injury, he found that there were no injuries on her body and no damage to her clothes.
Second, rape is a violation. Generally, ejaculation occurs within one or two minutes and does not last for twenty or thirty minutes.
In addition, raping on the lawn for so long will leave traces of grass and mud on the clothes. But I found none of these things on her clothes. This proves that after they had sex on the beach, JFK Jr. probably said they would never see each other again, and Patricia bit JFK Jr. in a fit of rage.