Helen Mo and Her Mother (Amy Sunmo)

Information on Helen Mo, Amy Sunmo, and Yi Chen (Eric) Liu

**NOTE: the information provided below regarding each document are summaries with some commentary to provide some context and connection to relevant facts of the case. It is advised that you view both the information below, as a supplement, and the actual documents to ensure full comprehension of Sonny's case. The summaries and commentary are used to provide an understanding of the case." 

**Color Code Legend for flag markers:

Pink (purple): Helen Mo’s direct statements, statements/description made by Helen Mo, and/or information relating to Helen Mo.

Yellow: information relating to the victim, Eric Liu, from this case, and any other victim information from Mo’s 1998 conviction, and/or victim-blaming remarks.

Green: Possible police or prosecution misconduct and ineffective assistance of counsel.

Orange (red): Gang-related information



Interview from Helen Mo p. 65 (p. 1): During Helen Mo’s interview, Investigator Montgomery asked Helen about her relationship with Sonny. Helen stated that she was dating Sonny back in November/December. She later told Investigator Montgomery that she was going to move to a condo complex, where Eric used to live.


Investigative Supplemental p. 1-6 (Bates Stamp: 000337-000342) (p. 2-12): p. 1: An investigator executed and served a warrant on 2/9/2000 at 0740 hours for the residence at 300 East Hellman #A in Monterey Park to be chemically processed for fingerprints. At the time, Tommy Mo, Helen Mo’s brother, told the investigator that he was moved out of the house and that his family had most of their items currently in residence move to 2907 Maxson, El Monte, which is near the victim’s (Eric Liu) residence.  

The investigator observed that most of the furniture from the residence was indeed gone, except for some items that were temporarily stored in the kitchen and some items in the upstairs bedrooms.

Officer Li and the investigator proceeded to interview Tommy Mo. Tommy went on to relate that he had arrived his residence on Hellman on 1/24/2000 at around 6:30pm. At the time, he heard a loud argument in the area up above the garage, which is the first floor. When he went upstairs, he found his parents at the dining room table in the kitchen and his sister, Helen Mo, seated in the computer chair immediately adjacent to the top of the stairway of the living room. Tommy proceeded to ask what had happened, and his father said, “Ask your sister.” The parents then told Tommy to look at the carpet, and Tommy noticed that there was some type of stain up towards the top of the area by the stairway. The stain appeared to be red in color. (The next page of the document is a redacted version of the previous page. The last page of the redacted version has some words or phrases blackened out).

p. 2: Helen Mo’s mother went on to relate that in the morning of 1/24/2000, when she and her husband had come back, four kids had walked in. They were 15 and 16 years of age. very young, Asian, and had spilled drinks somewhere on the first floor. At least one of the boys had said something in English, and Helen later told her mother that the boy said, “It’s all your fault that Sammy is in jail.” (The investigator believes that this reference is to Samuel Chang from Helen Mo’s 1998 conviction).

Tommy then stated that there was some type of carpet cleaning machine in the bathroom on the first floor. He was told that Helen had gotten the machine earlier and that Helen had called a friend to bring the machine to the house. The investigator asked Tommy on whether he recalled anything on Sunday 1/23/2000. Tommy stated that everything has been “pretty normal since Helen got out of jail,” where Helen would often talk on the phone at 1, 2, or 3:00 in the morning. Tommy was also asked about some items at the garage when a previous warrant was executed on 2/3/2000. According to Tommy, he was positive that their gas can was empty earlier because when he kicked it, it moved in a jerky motion. (The next page is another redacted version of the previous page).

p. 3: Tommy was then asked about the roll of duct tape that was located on the north wall of the garage in a cabinet. He recalled that the duct tape was approximately 1 to 1 ½ inches, which should have been a three-inch roll of tape when it was new. The roll of tape was last seen 2 to 3 weeks ago in the cabinets.

The investigator then spoke to Fennie, Tommy’s girlfriend. She had been told that teenagers had come into the house and spilled something, and that she and Tommy used some “409” cleaner and some stuff in the bedroom area to clean the carpet. She also stated that the stain in the carpet was burgundy in color, but they had made the color lighter.

p. 4:  According to Amy Mo, Helen Mo’s mother, “four people had come up the stairs. She described them as not being very tall and that one, the second of the four, had an almost shave head. She stated that when they were walking up the stairs, one was holding something in his hands, but she did not know what it was. She stated they walked out of the house and sped up after leaving the house. She asked Helen who the people were that came into the house.” When she first arrived home, Helen was sitting on the couch in the living room. Helen had told her mother that the stain in the carpet was a beverage. That’s when the boys came into the house, and one of the boys said something in English. Helen had told her mother that the boy had threatened her. When asked about the rental machine, she was not aware of it, other than seeing the machine in the bathroom and the next day. Later on, the mother and father took Helen to the “volunteer place” (El Monte Courthouse). (The next page is the redacted version of the previous page).

p. 5:  Amy was also asked about her activities with her husband on 1/24/2000. She stated that she left the house at approximately ten in the morning to buy groceries and later went to a restaurant. Amy was later shown a group of photographs of possible associates or persons who Sonny Wong had called in the area of January 24, 2000. Amy stated that she did not recognize any of the persons. When she was shown a picture of Sonny, she stated that she did not recognize Sonny nor recognize the name of Sonny.

When asked about the victim, Eric Liu, she stated that Eric had come to their house in the past, and that she had given Eric a “Moon Cake” around autumn or September. When asked about any beverages that she may have offered to Eric in the past, she stated that she did not think there were any items like that. According to Amy, Eric had been at their house approximately 2 to 3 times in the past, but no more than five times. The father, Bob Mo, was also interviewed later. He stated that he and his wife had left the house that morning at approximately 10, perhaps later, but no later than 10:30. After providing information about their activities that day, he stated that he and his wife arrived back at their house at approximately 12:30pm. (The next page is a redacted version of the previous page).

p. 6: According to Bob, he was in the restroom when there was a commotion outside. He heard his wife and Helen talking about the carpet, stating that there was a Coke stain on it. They tried to clean up the stain with a brush and some dishwashing detergent. Bob took Helen to the volunteering place and came back. He didn’t go back to the volunteering place until around 3pm with his wife. They took Helen back to the house with them and didn’t stop along the way. Bob took the cleaning machine back to the store with Helen the next day. (This portion of the page was an attempt to be redacted, as well as the next page).


Page 1 and 2 of TAPE #2, TAPE #3, TAPE #4 (p. 13-14): In Tape #2, Helen Mo stated that she recognizes Doug and Sonny in the pictures. According to Mo, Doug was an acquaintance. She further stated that she was dating Sonny. On page 2, Mo states that she dated Sonny around November, which matches with the information she provided in her interview on p. 65. However, on page 2, she stated that she took Sonny home for dinner and her parents did not approve. This information is inaccurate and contradicts with her mother’s (Amy) statement previously. Helen’s mother has stated in the previous pages that she did not recognize Sonny nor recognize the name of Sonny. This demonstrates that Helen lacks the credibility in her statements. This is confirmed with Helen’s polygraph test on page 1. The results showed that she failed her polygraph test. Detective Larry told Helen to tell the truth because he also feels that everything she had been saying is a lie.

The detectives, investigators knew that Mo was lying, and the polygraph results provided support for that. Yet, they still relied on her statements to “fit the pieces together” for this case. Relating back to a couple pages earlier, the investigators came to Helen Mo’s residence at Hellman on 2/9/2000 to have it chemically processed for fingerprints. By the time they arrived, Mo and her family have already moved to another location: 2907 Maxson Road. There was barely anything left at their residence in Hellman. This demonstrates that the evidence at Mo’s house in Hellman was already contaminated. In addition, on 1/24/2000, Mo and her mother were cleaning the stain on the carpet that was said to be from a spilled beverage. In the previous stipulation, Mary Hong indicated that Eric’s DNA profile was present in the carpet that was near the stain. There are plenty of obvious evidence at Mo’s residence in Hellman that identifies Mo as the guilty perpetrator for the murder of Eric Liu. However, the investigators failed to arrive on time to preserve the evidence and maintain the chain of custody. As a result, they rely on other people’s statements, like Helen Mo, to reconstruct the pieces together to fit their theory, even though some of those statements are unreliable.


Helen Mo 3rd Interview, 2/3/2000 at 1145 hours, p. 101-102 (p. 15-18): In the first page, Helen was asked about who would have seen Eric before he went to school on Monday, 1/24/2000. She responded with “Sonny. That’s the only person I can think of.” She further related that it didn’t make sense to her that Sonny would be in front of her house because her parents don’t like him.  (As previously stated, we see this information contradicted with Helen’s mother’s statement. Hence, this piece of information is false).

Helen continued stating that Eric has been over to her house maybe once or twice. This information is also false. As previously stated, Eric visited Helen’s residence approximately 2 or 3 times, but no more than 5 times, according to Helen’s mother. Helen was still insistent on stating that she and Sonny were dating from November and that her parents had approved of their relationship at the beginning. She also stated that she would go out with Sonny until she started coming home like at 3:00 in the morning. This statement is slightly false. According to Tommy in the previous pages, Helen was “pretty normal since she was out of jail,” and would often talk on the phone at 1, 2, or 3:00 in the morning.

Document Bates Stamp: 007965 (p. 19): On January 26, 2000, at approximately 1:00pm, Investigator Montgomery contacted Investigator Ken Whary from El Monte Police Department, who discovered a contact between Eric and Officer Legere from El Monte Police Department. This contact took place on December 16, 1999. At the time, Eric told Officer Legere that someone had used his credit card to purchase some merchandise. He told Officer Legere that it might have been his girlfriend, and that the charges were made at the West Covina Mall. Eric didn’t want to charge his girlfriend at the time. Officer Legere gave him some information in case he changed his mind.

Ying Hsi Lin, the victim’s mother, was contacted by Investigator Montgomery on January 26, 2000 at approximately 2:20pm. The victim’s mother stated that on January 24, 2000, at approximately 11:00 am, a woman called on their house phone and spoke in Mandarin Chinese, asking for Eric. The mother handed the phone to Eric and left the room. Eric stayed in the room for approximately 20 mins. before exiting.

On January 26, 2000, at approximately 4:45pm, Investigator Montgomery asked Helen when was the last time that she spoke to Eric. She said that she last spoke to Eric prior to the New Years millennium, which would be around December 1999. Helen told Investigator Montgomery that Eric seemed to like her more that she liked him, and that they were close before winter break of 1999. They stopped being close before Christmas 1999.


Irvine Police Department Case Work Sheet (Bates Stamp: 001218, 001223, 001161) (p. 20-22): The notes reiterated the victim’s mother’s (Ying Hsi Lin) statement about receiving a call around 11:00 by an unknown woman speaking Mandarin Chinese, asking for Eric. Helen Mo’s information was also provided, along with some notes on the last time that Helen spoke to Eric.

On 1/12/2000 at 2100 to 2200 hours, Eric borrowed Apple’s (Tony’s girlfriend) cell phone to talk to his sister. He went to the bathroom and turned on the fan. The call lasted 30 minutes, but Apple stated that Eric yelled and sounded very angry. She believed that Eric did not talk to his sister. The investigator also spoke with Tony, Eric’ business partner, who stated that on Saturday 1/22/2000 or Sunday 1/23/2000, Eric asked Tony to go with him somewhere on Monday 1/24/2000. Tony refused to go because he stated that he had school. According to Tony, Eric did not say what help he needed or when he needed help. (Based on the information provided, it seemed like Eric could have possibly spoken to Helen on 1/12/2000, but it is even more apparent that Helen was the one who spoke to Eric the morning of 1/24/2000 at around 11:00am because she is fluent in Mandarin Chinese and was close to Eric. Since Eric is aware of Helen’s background and gang affiliation from his friend, Alan Ou, he probably asked Tony to accompany him on 1/24/2000 for protection in case something happens to him). The notes also stated that an investigator spoke to Wei Wei, Eric’s female friend, at around 1205 hours. According to Wei Wei, Eric told her that Helen admitted to taking his credit card and gave it to someone else to make a duplicate. The duplicate card was then used at a mall in Arcadia, CA.

In another worksheet, an investigator indicated that the victim’s mother saw Eric leave at about 1100 hours. The notes also indicated that Tony previously drove a black Honda. This matches with the description that Helen Mo gave about seeing a black Honda at De Club.


People v. Mo, Severance Motion p. 5 (Bates Stamp: 380)(p. 23): On January 25, 2000 Investigator Cain spoke with Annie Liu, who is the sister of Yi Chen (Eric) Liu. Anne stated that she last saw her brother at 11:00 am on January 24, 2000. This statement contradicts with the previous page, stating that it was Eric’s mother who last saw Eric at 1100 hours before he left.

In addition, On January 26, 2000, Stanley spoke to Ellen O’Hara, who said that she was walking on Irvine Center Drive, when suddenly heard two bangs in an adjacent field. When she looked up, she saw a vehicle engulfed in flames, and a white 1980 Saturn, with oval passenger windows and Mustang-type rear brake lights, drive away. Instead of bringing a car that matches this description to Sonny’s trial, the prosecution alleged that Sonny’s white Honda civic was present at the crime scene. In a separate document, other witnesses have stated that Helen ex-boyfriend, Robert, owns a white Saturn car. However, this piece of information was never investigated nor brought to Sonny’s trial.


Document (Bates Stamp: 001262) (p. 24): These are some notes from an investigator’s notepad. The notes contain some information about the victim, Eric Liu, such as Annie Liu (sister) and Ying Lin (mother). As previously stated, Tony had a black Honda. However, it is also stated that the victim doesn’t have a girlfriend, which contradicts from previous aforementioned documents.


Document (Bates Stamp: 001267) (p. 25): These are some notes from an investigator’s notepad. It contains information about “Wei Wei”, “Wei-Chen,” and “Tony”. Moreover, it has been noted that Eric normally carry cash in his wallet.


Document (Bates Stamp: 001278) (p. 26): These are notes from an investigator’s notepad. The notes contain information about a gas can, Helen, Apple, and Tony.


Irvine Police Department (Handwritten Bates Stamp: 118-122) (p. 27-31): A tape recording was made at Irvine Police Department Custody Facility. The recording was of Helen and her mother, Amy, from February 3, 2000 at approximately 2015 hours. Here is a highlight of their conversation:

Helen: Mom how come…Did they talk to you?

Amy: A lot of people…What did they ask? You need to tell the police what’s going on.

Helen: What kinds of questions are they asking you?

Amy: I told them about what happened that day. I told them everything….How did you get involved in the murder?

Helen: I did not use (do) it, how could I kill someone?

Amy: Did you take away our gas can in the house?

Helen: What gas can? I don’t know what you are talking about.

Amy: The gas can in the house.

Helen: I don’t know. Why would I take the gas can for?

Amy: The deceased person was set on fire….How could you kill someone? Was it for revenge? What happened? Say something….How come you’re so cruel?

Helen: I’m not. What did you tell them? You need to tell me.

Amy: I saw the subjects came up the stairs.

Helen: And?

Amy: And then they left. (Note: “they” was never specified)…I told them they came to rob us. They (police) took everything.

Helen: You can’t say anything on the phone.

Amy: Why? What happened? How could you kill someone?

Helen? What did they take away?

Amy: I don’t know. They took everything.

Helen: Did they check for fingerprints? What happened?

Amy: How come the gas can is missing?

Helen: I don’t know.

Amy: The dead guy was burn with the gas from our gas can…

Helen: Did you tell them those things?

Amy: Yes, I told them everything.

Helen: What did you say? Did they test for anything?....

Amy:…How could you be involved in the murder? You need to tell the truth.

Helen: I know. I know. It’s not convenient for me to talk on the phone right now. I’ll talk to you later from somewhere else. The phone I’m on right now is a speaker phone.

Amy: You need to tell the police.

Helen: I know.

Amy: Did you?

Helen: No.

Amy: If no, how could the police be looking for you.

Helen: It’s not convenient for me to talk right now…

Helen’s mother is aware of what her daughter did and wanted her to tell the truth about her involvement with the murder of Eric Liu. However, instead of telling the truth to the police, Helen made sure that her mother did not say things that would contradict her statements. She had to verify with her mother if she had certain things and she wanted to know if the police had tested anything, as it would contain multiple DNA profiles (hers and the four people that came to her house that day).


Supplemental Report p. 2 of 7 (Handwritten Bates Stamp: 63) (p. 32): This document is redacted. However, Helen had stated that “they” knew where her parents were and where they lived and that even if they moved it didn’t matter. It seemed like she feared for her family’s safety at the time. Instead of telling the truth of what had happened that day, Helen said, “If I say I killed him is the case over, will you still investigate?” Based on this statement, it seems like Helen is trying to cover up for someone by taking all the blame. She is afraid that if she reveals who the real additional perpetrators were, her family would be harmed regardless of where they live. If that is the case, why did she give up Sonny? If Sonny was indeed involved in any part of the murder or plotting of it, why wouldn’t Helen Mo be fearful of Sonny? This is because Sonny does not have any involvement in the case, and Helen is using Sonny as a scapegoat to protect the other perpetrators from getting caught. Helen has stated in a later document that if “any of them” get caught, her whole family will get greenlighted. Greenlighted is a gang terminology that is used to signal gang members to eliminate certain people.

She later stated, “It’s me. I’m stupid. I had to open my big mouth out of frustration, worried. I didn’t know this would happen. I would never kill anybody.” Helen also stated that on Monday (1/24/2000) after school, she called Eric and asked him to meet with her and he agreed. (Helen seems to be contradicting herself previously, where she stated that she last spoke with Eric on the New Year’s millennium, which was a false statement).

Mo also stated that Eric wanted his family necklace back and she had offered money. This piece of information will later contradict with another co-defendant’s, Souriyo Banthakounh, sister (Victoria Banthakounh) who stated that Helen did not want to return the money to the victim, Eric Liu.


Helen Mo, Amy Sunmo, and Yi Chen (Eric) Liu.pdf