MODESTO, Calif. (KGO) -- Well before last weekend's murders, Martin Martinez was already being investigated for the death of his ex-girlfriend's two-year-old son.
Modesto police knew time was wasting in the unsolved death of a child and then the unthinkable happened, a mass-murder possibly committed by the same person of interest, so they obtained an infrequently used arrest warrant.
Modesto police detectives spent more than an hour at the San Jose home where Martin Martinez's father and uncle live. Police arrested him early Sunday morning at a mall in San Jose after they discovered the five bodies in the Modesto home of his former girlfriend Dr. Amanda Crews.
Police captured him, not for those murders, but because of suspicions that he killed Crews' two-year-old boy in October. Last Thursday, two days before the mass murders, a medical expert told police it looked like homicide. No arrest warrant was issued until two days later when police made their grisly discovery.
Modesto police say they did not drop the ball and that Martinez had no reason to believe they were closing in on him.
Lawyer Dennis Luca is a former cop. He believes Modesto police wanted more than just a medical expert's evaluation.
"I don't know if the neurologist has the ability to state cause of death with certainty. That's why we have coroners," Luca said.
Police quickly obtained a Ramey arrest warrant, which allows them to bypass the district attorney's office and go directly to a judge.
"It's an unusual police procedure but it was done for two reasons, to see if he'll talk but to get him off the streets for a while, particularly since this second incident occurred," said Stephen Clark a legal analyst.
The judge who signed the Ramey warrant also gave authorities until Thursday to hold Martinez, which allows prosecutors until then to file formal charges against him.