In closing arguments Thursday, prosecutors cited evidence of semen on the victim's underwear to counter defense claims that the officer, Michael Pena, didn't have intercourse during the assault.
The defense said the 25-year-old victim was in such "abject terror" after Pena threatened to "blow her face off" if she looked at him that she was mistaken about being penetrated.
Pena, who is charged with predator sexual assault and rape, has admitted attacking the woman but claims he didn't have intercourse with her during the assault. New York law imposes lighter punishments on would-be rapists who fail to complete the act.
Authorities allege Pena approached the woman at about 6 a.m. on Aug. 19 in upper Manhattan's Inwood neighborhood and asked her how to get to a subway stop. They say he then grabbed her, showed her his gun, ushered her several blocks to an apartment building backyard and raped her.
A resident of the building called 911, saying she saw from her window that something was amiss in the yard.
When officers arrived, the teacher ran to them and warned them Pena was armed, police said. Officers didn't realize Pena was a colleague until they found his police ID upon arresting him, they said.
Pena joined the New York Police Department in 2008. He has been suspended without pay and is being held at the Rikers Island jail on $500,000 bail.
Pena's case is the second rape trial involving city police officers in the last year. In May, a jury acquitted Kenneth Moreno and Franklin Mata of raping a woman but found them guilty of official misconduct, a misdemeanor.
The two were called to help the drunken woman get out of a cab in December 2008. The woman said she passed out and awoke to being raped.
Moreno said he cuddled with her in her bed but there was no sex. Mata said he was napping on her sofa.
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