A Tucker man went on a 20-hour crack drug binge after bludgeoning his girlfriend to death last week, Gwinnett County police said Thursday.

Shannon Marlow, 33, is accused of killing his girlfriend, 47-year-old Patricia Rabold, inside her Norcross house.

Kimberly Smith/AJC (ENLARGE)

Melissa Painter (center) reacts after hearing the details of her aunt, Patricia Rabold's death. Stephanie Patrick (left), also Rabold's niece, and Michael DuPont (right), Rabold's former husband, listen.

Kimberly Smith/AJC (ENLARGE)

Shannon Marlow is escorted into Gwinnett Magistrate Court.

RELATED: Photos: Marlow in court Story: He beat her to death Gwinnett news • State and local news

Police detective Steven Shaw testified Thursday at a preliminary hearing in Magistrate Court that Marlow left the house, drove to Tucker to use cocaine and methamphetamine, then returned to the Edgemoor Drive house where he'd left Rabold's body lying on the foyer floor.

Shaw said Marlow initially told detectives he went to buy milk at a convenience store Feb. 13 and returned to Rabold's home to find her dead.

Marlow said that after he walked inside, someone hit him on the back of the head, Shaw testified. Marlow said that he passed out and woke with an ax in his hand, Shaw testified.

After detectives started pressing him on the details, Shaw said Marlow's story fell apart.

"That's when he shifted gears and said, 'I'll tell you the truth: I killed her,' " Shaw said.

Marlow allegedly struck Rabold on the head repeatedly with both the blunt and the sharp end of an ax.

Marlow has a history of arrests dating to 1992 in Gwinnett. Court records from those cases show he was diagnosed as a schizophrenic and that by age 18 he had been in and out of psychiatric treatment centers.

Shaw testified Thursday that Marlow told detectives he was in a "state of paranoia" when he attacked Rabold.

"He believed that Rabold and another man in the house were out to kill him," Shaw testified.

A judge ruled there was probable cause to bind over to Superior Court one count of felony murder and one count of theft by taking against Marlow.

After the hearing, Rachel Rabold, Patricia Rabold's 22-year-old daughter, emerged from the courtroom surrounded by about 10 other teary-eyed relatives. Rabold said she attended the hearing because she wanted to hear for herself what had happened.

"I want to make sure he's behind bars for the rest of his life," Rachel Rabold said.