A man who allegedly stabbed his wife to death with a pair of pliers and a woman who allegedly set fire to her girlfriend’s home, killing the two children trapped inside, await judgment by two juries after their respective trials ended with lawyers’ closing arguments today.

DA LIN HUANG (D.O.B. 3/16/63) is charged with first-degree murder for the homicide of his 30-year-old wife, Gin Hua Xu, in his Allston apartment on the afternoon of Jan. 27, 2001. Xu was stabbed repeatedly with a pair of electrician’s pliers and her body was mutilated after her death.

NICOLE CHUMINSKI (D.O.B. 5/19/82) of South Boston is charged with two counts of first-degree murder for the deaths of 14-year-old Acia Johnson and her sister, 2-year-old Sophia Johnson, in an April 5, 2008, house fire. Chuminski, who allegedly used an accelerant in setting the blaze, is also charged with arson and two counts of assault and battery with a dangerous weapon – smoke and fire – for non-fatal injuries sustained by the girls’ mother and brother.

By pure coincidence, the two trials of fatal domestic violence opened together on Feb. 1 and ended together today. Jurors in both cases received the evidence early this afternoon and will resume their deliberations on Tuesday.

Speaking in his closing argument, First Assistant District Attorney Josh Wall asked if a murder case could be so strong that it could be proven without words.

“Can the truth,” he asked, “be so evident that it speaks directly to you?”

In response, the lights were dimmed and the prosecutor placed a series of photographs on a display screen. One by one, he displayed to the jurors 16 photographs depicting the violence done to Huang’s wife in her final moments.

Then he held aloft the pliers Huang allegedly used to stab her upwards of 40 times before finally strangling her to death.

Then he showed jurors a foot-long sharpening rod that Huang allegedly used to mutilate her dead body.

“This case is so strong it can be proven without words,” he said to the jury. “When you walked into this courtroom two weeks ago, you didn’t know what first-degree murder looked like. Now you do.”

Wall told jurors that the defendant had a plan that included removing witnesses from the area, killing his wife, degrading her, and then killing himself by overdosing on prescription painkillers.

“He never wanted these facts before a jury,” the prosecutor said. “But that was the one thing he didn’t do right. The EMTs came too soon.”

Wall blasted the notion that Huang was not responsible for his actions because of mental illness.

“Think of the testimony of the people who knew him best,” he said. “[Family members] described a high level of functioning in the time leading up to the crime. [Doctors] described no abuse of medications. No sign of brain injury. No sign of depression.”

Wall pointed to the testimony of the defendant’s and victim’s son, who described arguments between the pair that were so violent the little boy tried to get between them.

“How much rage is apparent there,” the prosecutor asked. “He’s physically assaulting his wife with his son hanging off of him. That’s the anger in Da Lin Huang in the weeks leading up to the crime – physically assaulting his wife to take money from her with his son hanging off of his leg.”

Huang was humiliated, Wall said, by the fact that Xu was seeking a divorce and, in effect, airing for others her dissatisfaction with their relationship.

“That’s what happened to Gin Hua Xu when she disagreed with him privately,” Wall said. “Can you imagine what it did to him when she put it out there publicly with a separation?”

Huang was not out of control, Wall said.

“The problem was that he could not control her,” the prosecuted told jurors. “And that was the motive.”

One floor above the Huang case, another prosecutor recounted the case against Chuminski, who allegedly set fire to her girlfriend’s home after a fight at a wedding the prior afternoon. Chuminski’s girlfriend, Anna Reisopoulos, escaped with her son; her two daughters were trapped inside and perished in each other’s arms.

“Every piece of evidence points to one person and one person only,” Fredette said, “and that’s Nicole Chuminski.”

Fredette described for jurors how on the evening before the fire, Chuminski and Reisopoulos had gone together to the wedding of one of the defendant’s relatives. While they were there, an incident occurred that resulted in the defendant’s family asking Reisopoulos to leave. Fredette said that as a result, Chuminski, “was embarrassed, she was humiliated, and she was later kicked out herself.”

Fredette told the court that, Chuminski made her way from the wedding location in Weymouth to South Boston a few hours after the wedding ended and started banging on Reisopoulos’ door. When she got no response, she attempted to call the victim’s cell phone, to no avail.

Chuminski eventually left the West 6th Street home and went to a friend’s house, “and all she kept talking about was the wedding and [the incident],” Fredette said. “She has drugs in her system, and she’s angry.” Sometime between 2:30 and 3:00 a.m. on April 6, Fredette said, Chuminski returned to the victims’ home, and tried calling the victim again.

“She’s banging on the door, no one’s answering, and the kids aren’t supposed to be there,” Fredette said. “She wants to send a little bit of a message. She takes something with acetone in it and pours it on the steps and lights it. This was an intentionally set fire.”

“The defendant set this fire, and there is no doubt at all that this was an arson. There’s no doubt that it’s a murder,” Fredette said. “Who would do that? There’s only one person – just Nicole Chuminski. It’s hard to believe, it’s hard to fathom, because there are two kids who died.”

In the aftermath of the fire, investigators from the Boston Fire Department and Boston Police Department determined that the fire had been deliberately set. Evidence from the scene was brought to the Massachusetts State Police Crime Laboratory, where chemists found the presence of acetone – a chemical found in many solvents.

When investigators interviewed Chuminski about the fire, Fredette said, she “tried to distance herself” from the crime and changed her story to police multiple times. Her clothing from that night were seized and tested positive for acetone.

Fredette told jurors to dismiss “remote speculation that some other person, a mystery person, would light a fire at that particular moment after these two women had a fight. Is that reasonable?” he said. “The answer is ‘no’.”

Asking the jury to find Chuminski guilty, he pointed at the defendant and said, “This was the person that started that fire, and those two kids died because of her actions.”

Catherine Yuan is the DA’s victim-witness advocate assigned to both cases. Huang is represented by attorney Larry Tipton with Judge Christine McEvoy presiding in courtroom 808. Chuminski is represented by attorney William White with Judge Frank Gaziano presiding in courtroom 906.