Lyons, 45, sighed when Judge Vincent Gaughan announced he'd get the maximum sentence.
Lyons was charged in his daughter's death in 2011 . He was not initially a suspect, but police and prosecutors say that within days, his story started to unravel and his actions seemed inconsistent with a grieving father. Then, came blood spatter evidence. Those two things together were the case against Richard Lyons.
Lyons' attorneys rested their case without presenting a witness. It took a jury less than two hours to find Lyons guilty.
''What makes this particularly heinous is the fact that this crime was not only committed against a young child, it was committed by her own father who she should be able to trust and rely upon,'' said Fabio Valentini, assistant state's attorney.
Lyons wasnt arrested until three years after his daughter's death and his relatives say that Mya's murderer is still out there.
''The police department personally dropped the ball when it took them four and a half days to secure a crime scene,'' said Valerie Tines-Lyons, Richard Lyons' aunt.
Before arresting Lyons, police arrested a drug addict for the crime, however, that man was never charged after tests showed the blood on his shoes was his own.
There was no clear motive for the murder of Mya Lyons, a case built on circumstantial evidence, and most significantly, blood spatter evidence. Traces of Mya's blood found in Richard Lyons' van indicated that Mya was stabbed repeatedly in the van, and that her father had done that to maker it appear as though someone else had murdered his daughter after he had earlier delivered a fatal blow to her head.
"There's two reasons why he stabbed her. He had beaten her and she was still alive, he thought, and he stabbed her to keep her from telling her story. And he also stabbed her in the way he did to make it look like some crazy person wandering through an alley had killed her," Valentini said.
Lyons sat expressionless after the verdict. His family says the jury had not paid attention, justice was not done, and that he never would have harmed his daughter. But the defense claim that a burglar killed Mya was dismissed by prosecutors as ridiculous. Her mother believes justice was served, but will forever grieve.
"I will never understand why, but my daughter wanted us to know what happened to her," said Barnes. "The verdict we've waited for six years: guilty, guilty. And he's going to pay for what he did to my baby."
The state's attorney says the blood spatter evidence was critical in this case, that's what led to Lyons' arrest three years ago.
Barnes spoke in the courtroom on Friday, saying she believed Lyon's deserved life in prison. She paused frequently and fought to hold back tears as she explained how Mya's younger brother, Omari, will have to grow up without a big sister. Barnes she has sleepless nights, waking up crying.
"I believe the defendant is a coward and a psychopath who should never be allowed out," Barnes said.
''It's sad to say it was the dad, her father, but I'm glad for the peace for my daughter and the peace for all of us,'' said Estella Bradley, Mya's grandmother.
Lyons' is also accused of sexually abusing a teenage boy and awaits another trial for this unrelated matter.