The suspect in their murders? Their 17-year-old son.
In two weeks, a judge will take the next step in the judicial process for the teen - deciding whether or not to charge him as an adult. The teen's attorney maintains his innocence.
ABC13 legal analyst Joel Androphy says the decision to charge a juvenile as an adult is not easy.
"In large part the court is going to look at the serious nature of the crime," Androphy said.
Furthermore, a judge must factor in the safety of the juvenile if they are certified as an adult.
"You can't certify somebody as an adult if they have the maturity of a 12-year-old, for example," Androphy said. "Because if the person is convicted, you can't put a person with the maturity of a 12-year-old in the Texas Department of Corrections or subject them the adult probation system. The person is never going to survive."
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In the case of the Antonio and Dawn Armstrong, their teenage son will likely go through several tests before a decision is made.
"There will be mental testing, psychiatric testing, physical testing, checking with neighbors and schools, family and friends to determine the level maturity of the child," Androphy said.
CASE OF MIGUEL NAVARRO:
Miguel Angel Navarro was sentenced to 99 years in prison for the 2007 murder of Matthew Haltom. At the time of the murder, Navarro was 15 years old.
During the investigation, police said Navarro was an uninvited guest at a bonfire and party in the 2000 block of Saddle Horn Trail in Katy.
A confrontation unfolded and Haltom was stabbed to death.
In October 2008, Navarro was certified to stand trial as an adult.
WHAT HAPPENS IF A JUVENILE IS CHARGED AS AN ADULT?
With the passing of Senate Bill 888 in 2015, juveniles have an instant way of responding to a judge's decision. The bill allows for juveniles to immediately appeal a certification to be tried as an adult. Prior to 2015, a juvenile had to wait until they were found guilty to appeal the certification as an adult.
"When the state decides to try a juvenile as an adult, we want to provide certainty that the right decision was made," Senator Juan Hinojosa said in a release. "Senate Bill 888 gives certainty to the important certification process and protects juveniles from having to face the consequences of being in adult criminal proceedings if they don't belong there."
The state of Texas' Family Code also gives strong credence to judicial proceedings. Those can be found in sections 51 through 61. null