OAKLAND (CBS SF) — An Oakland man was convicted Tuesday of voluntary manslaughter for fatally stabbing his sister’s boyfriend during an argument over loud music last year.

Prosecutor Scott Ford asked jurors to convict Van Surrell, 22, of murder for the death of 22-year-old Blair Robertson at an apartment in the 700 block of East 11th Street in East Oakland on Feb. 16, 2013.

But jurors, who deliberated for only one day, found Surrell not guilty of both first- and second-degree murder and convicted him of the lesser charge of voluntary manslaughter.

One of Robertson’s family members cried after the verdict was announced in a tense courtroom that was guarded by six bailiffs. Meanwhile, two of Surrell’s family members held hands and smiled after he was acquitted of murder.

Surrell’s lawyer, Darryl Stallworth, who put his arms around Surrell’s shoulders when the verdict was read, said afterward that he thinks Surrell should have been found not guilty of all charges because he believes that he acted in self-defense.

But Stallworth said he’s also “happy that they saw that this was not murder” because he believes Surrell didn’t intend to kill Robertson.

Stallworth said Robertson and Surrell got into an argument on Feb. 13, 2013, because Robertson was playing music too loud and refused Surrell’s request that he turn it down.

Stallworth said the two men then challenged each other to fight and Surrell grabbed a knife to protect himself because Robertson had beaten and choked him in previous confrontations.

However, the defense attorney said Robertson then turned into the knife that Surrell was holding and suffered wounds that took his life.

Surrell, who also was convicted of an enhancement clause that he used a knife to kill Robertson, faces up to 12 years in state prison when he is sentenced by Alameda County Superior Court Judge Stuart Hing on Aug. 21.

He would have faced 15 years to life if he’d been convicted of second-degree murder and 25 years to life if he’d been convicted of first-degree murder.

The prosecutor wasn’t immediately available for comment after the verdict.

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