Shannon Crawley's defense team told the jury Friday that Smith's fiancé is the real killer. Crawley and the fiancé - Greensboro police officer Jermeir Stroud - also had a relationship.
Stroud has admitted dating both women, but denies involvement in the killing.
Friday, defense attorney Scott Holmes challenged Stroud's credibility on the stand and told the jury that police rushed to judgment - failing to rule him out as a possible suspect.
"If you have a suspect who you can't prove or disprove did it, that's reasonable doubt," said Holmes.
Holmes said investigators failed to prove that Crawley even knew Smith.
Smith was shot in the head at Campus Crossing Apartments in Durham in January 2007.
Prosecutors say Crawley stalked and killed Smith out of jealousy. In their closing arguments, they said there was no reasonable doubt that Crawley pulled the trigger and asked jurors to return with a guilty verdict.
Superior Court Judge Ronald Stephens gave his jury instruction Friday afternoon. Crawley faces a possible life sentence if convicted.
After the jury asked to see charts, photos and diagrams, they ended deliberations around 5 p.m.
The judge told jurors specifically not to go back to the scene of the crime over the weekend. The insturction came after the judge denied jurors' request to take a field trip to Denita Smith's apartment where she was shot.
Deliberations will resume Monday at 9:30 a.m.