DALLAS (KRLD) -- Dagoberto Castañon and Rogelio Avila were arrested in Florida and charged with murder last month for the April 15 hit-and-run crash that killed a 13-year-old boy in Dallas.
Now, Avila has been set free.
Avila posted $25,000 bond on a probation revocation charge on Saturday and was released.
A statement from the Dallas County District Attorney says investigators have determined that Avila was not the driver.
Former prosecutor Toby Shook says it appears that Avila has flipped on his co-defendant.
"Apparently their investigation has led to their belief that the other suspect is the driver, so they want the co-defendant's help in getting them evidence," says Shook.
Castañon remains in custody.
Investigators believe that both Castañon and Avila were in the van that fled from police in Highland Park and crashed into the car carrying Ethan Vazquez and his mother, Sandy.
Ethan died at the scene. Sandy was transported in critical condition to a local hospital, where she continues to recover.
The two suspects were caught in a trailer park in For Myers, Florida by U.S. Marshals.
Shook says it's highly unusual to allow someone to post bond out of state in a murder case.
"Apparently there's been no bond made on the murder charge," says Shook. "The major question is, what happened to that murder charge?"
In a statement, a representative with Dallas Police said they are aware of Avila's release.
"We continue to work with the Dallas County District Attorney's office for a successful prosecution of Ethan Vasquez's murderers."
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