With no eyewitnesses who saw Met with the child the day she was killed, prosecutors have pointed to this evidence as proof that Met killed the girl.
Met, 27, is charged in 3rd District Court with first-degree felony child kidnapping and aggravated murder. If convicted, he could spend the rest of his life in prison.
But defense attorneys countered that the girl's blood on the back of Met's jacket proved little.
No blood was found on the garment's front or its sleeves, DNA specialist Chad Grundy said. Met's pants and white T-shirt were clean.
The jacket, Met's family testified, was the only one he owned.
The defense has suggested Met's clothing was stained well before Hser Ner Moo disappeared, during a game of elephant ride, in which Met would carry the child and her friend atop his back.
Met's lawyers have said the skin cells collected from under Hser Ner Moo's fingernails were also a result of such play, wherein the girl may have accidentally scratched Met's skin.
"Is it possible if someone were giving a child a ride on their back and the child's nose began to bleed that you would end up with four spots of blood in a line like this?" West asked.
"I can't say that it's not, because it could be possible," Grundy said.
But prosecutors suggested the skin cells and blood drops hint at something more sinister.
Holli Barbera, a registered nurse, was called to examine Esar Met's body for signs that a sexual assault may have taken place after Met was arrested on April 1, 2008.
She testified Wednesday that Met's skin showed signs of redness and scratches. His right shoulder was bruised, marks lined his legs.
"These marks are much smaller than I would expect to see if it were an adult scratch," Barbera testified. "It could be [from a child]."
Defense attorneys asked whether he could have suffered these injuries from being handled roughly by the officers who arrested him.
Some, Barbera said, could have. The others, defense attorneys implied, may have been caused by Met himself.
Prosecutors have alleged Met violently assaulted Hser Ner Moo physically and sexually before killing the girl and leaving her crumpled body in his blood-stained bathroom.
The scratch marks on his legs, the prosecution said, were a result of Hser Ner Moo scratching Met during that assault.
No DNA evidence was found to suggest a sexual assault took place, experts testified. But there wouldn't have to be any for a sexual assault to have taken place, a child abuse expert told the 11-member jury last week. Physical injuries to her genitals suggested a violent assault with "forceful penetration," testified Lori Frasier.
Forensic tests on the bloodstains found in the bathroom and on the apartment's basement walls, floor and bathroom belonged to Hser Ner Moo, DNA evidence showed.
Grundy testified Wednesday that the chance of it being anyone other than the little girl was slim one in more than 3.9 quadrillion.
But in several places in the basement where forensic analysts collected DNA swabs, the child wasn't the only DNA profile present, Grundy said. Most samples were too faint to tell who they might belong to, save one: a DNA sample collected from the west wall of the basement.
There, Grundy said, experts were able to exclude everyone in the home as being possible contributors including the defendant except for roommate Ku Nu. Prosecutors said Ku Nu likely left traces of his DNA when he chewed, and spit, a South Asian tobacco-like substance called betel nut around the home. Ku Nu also lived in the basement before Met moved in less than a month before the murder.
Bloodstains became the subject of an early morning motion by the defense for a mistrial in the case when defense attorneys learned of new evidence.
The evidence, a dark red stain found in the upstairs of Apartment 472, could have been "potentially dramatically earth-shaking mitigating evidence," defense attorney Michael Peterson said.
Tests by the state crime lab indicate that the upstairs stain may be blood.
But until Wednesday, testimony indicated that all bloodstains in the apartment were found in the basement.
"This spot they're talking about now has just this morning been identified to the defense as a blood spot," Peterson argued before 3rd District Senior Judge Judith Atherton. "Heretofore all information provided to the defense was it was not."
Although the case was first investigated in 2008 and has been pending in state court for nearly six years, the stain found upstairs was examined just this week.
It had not been collected at the time of the crime to be submitted for further DNA testing.
If it had and proved to be Hser Ner Moo's blood, defense attorneys argued, the stain may have pointed to a different assailant in the murder.
But now no one may ever know.
"Of course we're deeply troubled by this," defense attorney Denise Porter told the judge.
Grundy, who works for the state crime lab, testified Wednesday that he didn't take a swab of the upstairs stain to preserve and later determine its origin because the "main crime scene" was the basement.
A preliminary on-scene test determined the substance was likely blood, but Grundy didn't disclose this information to police or prosecutors until 8 p.m. Tuesday.
"As we were walking around, we noticed a lot of reddish-brown liquid in jugs throughout the upstairs area," Grundy said, referring to the jugs of betel nut juice. "But we felt that spot was close enough to the area with these jugs of red liquid that that's probably what it was. It wasn't the area we needed to focus on, so we concentrated our efforts on the downstairs."
Grundy made note of the stain's existence in his own files, but prosecutors and defense attorneys would have had to file a GRAMA request to see those documents.
"If that blood were tested and it were Hser Ner Moo's blood, it would vastly impact the composition of this case, wouldn't it?" West asked in cross examination.
"In my opinion, no," Grundy said.
Met's lawyers asked the judge to declare a mistrial in the case. But withdrew their motion by the afternoon, when they told a judge they could not prove the state withheld the information intentionally.
Prosecutors said Wednesday that they didn't know it existed until Tuesday.
The potential blood stain was the first of two new pieces of evidence introduced early Wednesday, the seventh day of testimony in Met's murder trial.
Footprint specialist Trent Grandy from the Utah State Crime Lab was called to the stand for a second time Wednesday to explain new findings to the jury regarding a footprint found on the carpet in the basement where the child was found dead.
Last week, Grandy testified that the footprint taken from the plush carpet matched that of the defendant's.
His lab, however, did not compare the print to those of Met's four roommates until this week.
On Wednesday, Grandy took the stand for a second time to testify that the four men who lived with Met "could not be excluded" as the footprint's source.
"The bottom line is these prints could have come from anybody in this house?" asked defense attorney John West.
"I could not exclude that possibility," Grandy replied.
Met's defense team has implied that Met's four roommates may have more to do with Hser Ner Moo's disappearance than they let on.
Under oath Tuesday, the four men testified that they didn't know the girl had been missing for as long as she was when police found her lifeless body in the bathroom below.
The men, who, like Met and the girl, are Burmese refugees, had been living in the apartment for nearly a year.
Some said they noticed an increased police presence in the South Salt Lake community where they lived but didn't realize it was a wide-scale search for the child until police found her body in their home.
Esar Met timeline
March 31, 2008
• 1:30 to 2 p.m.: Hser Ner Moo last seen by her family.
• 2:39 p.m.: The latest Esar Met could had left his South Salt Lake apartment to catch a bus to Cottonwood Heights, where he stayed the night at the home of his aunt and uncle.
• 3:30 to 4 p.m.: Esar Met arrives at his aunt and uncle's home.
• 6:30 to 7 p.m.: Hser Ner Moo's father, Cartoon Wah, knocks on the door of Esar Met's apartment; Met's four roommates said they hadn't seen the girl.
• Evening: Hundreds of volunteers scour the area looking for the 7-year-old girl.
April 1, 2008:
• 4 a.m.: Detectives knock on the door of Apartment 472 , get no response.
• 7 p.m.: Hser Ner Moo's body found in Esar Met's basement apartment.
• 10 p.m.: Esar Met arrested at his aunt and uncle's home.
A Missing Peace
Reporter Julia Lyon traveled to Thailand to trace the journeys of Hser Ner Moo and Esar Met from the Mae La refugee camp to Salt Lake City. Her series, reported in collaboration with the International Reporting Project, also explored the challenges their families and other refugees face in America. See the series at http://extras.sltrib.com/thailand.