Search dogs are scheduled to return to the site Wednesday night to renew efforts to locate Hacking's remains.
From the day Lori Hacking disappeared, police never referred to her husband as anything other than a "person of interest" — even as the lies he told relatives unraveled and his psychological condition deteriorated.
Authorities on Monday arrested Mark Hacking on one count of murder in the death of his pregnant wife even though they haven't found her body. He was picked up before his scheduled release from a psychiatric ward at the University of Utah Hospital and denied bail.
"We've actually been ready to make the arrest, probably could have made it sooner had he been released from the hospital sooner," said Police Chief Rick Dinse, adding that Hacking's 13-day hospitalization gave detectives more time to conduct their investigation.
Lori Hacking, 27, an assistant stockbroker, has not been seen since late July 18. Mark Hacking reported her missing the following day, telling family, friends and police she failed to return from a morning jog at a park near downtown.
Cracks soon emerged in his timeline, and police later said it was likely Lori never made it to the park. "We believed very early in the investigation that she may have been a victim of a crime, and her husband may have been responsible," said Dinse.
Detectives identified a motive and have found the weapon that killed Lori Hacking, Dinse said. He declined to elaborate.
Both Dinse and the Salt Lake County district attorney's office said failure to find the body would not keep the case against Hacking from proceeding, though there are questions how they would show aggravating circumstances, such as killing for personal gain or to elude arrest, or carrying out the crime in an exceptionally heinous manner.
Lori Hacking had told friends that she was five weeks pregnant, but police said she had not confirmed a home pregnancy test by visiting a doctor. If her body is found and the pregnancy is confirmed, prosecutors could add an additional murder charge, Dinse said. That might satisfy the condition for aggravated circumstances.