A Santa Fe jury has acquitted a 31-year-old man of killing a preschool teacher who intervened to stop a fight with his girlfriend, but he will be retried on two lesser charges.

Adrian Gonzales was acquitted Wednesday evening of first- and second-degree murder in the 2011 fatal stabbing of 21-year-old Victoriano Moises Byrne-Gonzales.

The jury could not reach verdicts on charges of involuntary manslaughter in the killing of Byrne-Gonzales and aggravated assault with a deadly weapon in the stabbing of another man. A mistrial was declared on those counts.

Prosecutors say Byrne-Gonzales was trying to do the right thing when he was stabbed in the neck while attempting to stop Gonzales from beating Gonzales' girlfriend, while defense attorney Joseph Campbell said Gonzales was defending himself.