Video cameras recorded the defendant and the victim together. Four women testified about his past patterns of sexual assault. His movements fit neatly into a timeline that tracked the killing.

But the best evidence against Demetrius Shaffer, the prosecutor said, came from a witness who never took the stand – the slain victim, Rajneet Kor Singh.

The 37-year-old woman had been strangled and sexually assaulted on a cold and rainy predawn New Year's morning and left for dead on a wet sidewalk behind a red-brick wall. But it was her fight for life that produced what authorities described as a forensic slam-dunk against Shaffer.

"You will never hear her voice explain how the defendant raped and killed her," Deputy District Attorney Thienvu Ho told a Sacramento Superior Court jury in his closing argument Tuesday, before Judge Maryanne G. Gilliard sent the panel out to begin deliberations.

"But with all her might, she fought for her life. With all her might, she scratched the defendant, and with all her might, she left behind the clues for each and every one of you about who her killer is."

Scrapings investigators retrieved from under Singh's fingernails contained the defendant's DNA, and forensic analysts found a single strand of hair loaded with Shaffer's genetic bindings on the victim's body. The prosecution also presented videotape from the Rancho's Club Casino showing Shaffer and Singh walking in together at 3:31 a.m. on Jan. 1, 2011, playing at a table at 3:33, walking out at 3:39 a.m. and then meandering down the street at 3:45.

Singh's partially nude body was discovered seven hours and 15 minutes later, about a block south of the casino that fronts Folsom Boulevard at Mills Park Drive in Rancho Cordova. She had been strangled – probably with her own scarf – and sexually assaulted.

Assistant Public Defender Michael Nelson insisted on Shaffer's innocence. The defense attorney said Shaffer and Singh had exchanged intimacies several hours before they arrived at the casino. Nelson acknowledged their presence together on videotape, but he said they later separated. He said Singh went to meet a jealous boyfriend. An acquaintance even implicated the boyfriend in Singh's death, Nelson told jurors.

Nelson said the spot where Singh's body was found – on the other side of the light-rail tracks from the casino and behind a brick monument advertising a housing development – is the last place in the world any man would want to take a woman for a tryst.

"I can't imagine a situation that is more unconducive to sexual activity," Nelson said. "Why would anybody commit a murder behind there?"

Shaffer and Singh ran with a Rancho Cordova crowd that indulged in methamphetamine and hung out in abandoned apartments and lived in area motels. Neither of them worked.

They met up in the first hours of 2011 at a friend's apartment across the street from the casino. After a methamphetamine smoke, Singh and Shaffer headed over to the card tables.

Ho told jurors the meth and the gambling money Shaffer gave Singh came "with strings attached and expectations." When she said no to his demand for sex, he strangled her, Ho said.

Despite Shaffer's lack of any adult convictions, Ho painted the defendant as a serial sex criminal. Besides the seven-count sexual assault case related to a second alleged victim in the current trial, the prosecutor produced three former spouses of Shaffer who testified to Shaffer's sexual violence against them.

Nelson said the alleged rape was really a consensual encounter and that the uncharged spousal rape allegations have nothing to do with the trial at hand.

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