A GPS monitor strapped to the ankle of convicted sex-offender Brian Golsby provided investigators with "a road map" that helped them obtain a death-penalty indictment against him Friday in the abduction, rape and murder of a 21-year-old Ohio State University student.

The GPS monitor also was critical in the decision by the Franklin County grand jury to charge Golsby with six armed robberies, mostly in the German Village area, that occurred in the days leading up to the slaying.

In the homicide case, the data showed that Golsby spent about an hour walking on the night of Feb. 8 from the campus area to the Short North before he kidnapped Reagan Tokes as she approached her car on East Third Avenue, just east of North High Street, Prosecutor Ron O'Brien said.

"It would appear to me that night he was trolling the entire neighborhood looking for someone like her who was alone in an environment that he could prey upon," he said.

Investigators were able to retrace Golsby's movements from Tokes' abduction at about 9:45 p.m. until her body was dumped near the entrance to Scioto Grove Metro Park in Grove City around midnight. Golsby was at the park for only three to five minutes, O'Brien said.

"I believe she was killed at the park," although the rape likely occurred elsewhere, he said.

Golsby, 29, is charged with aggravated murder, kidnapping, aggravated robbery, rape, tampering with evidence and having a weapon despite a felony conviction in Tokes' slaying.

Columbus police robbery detectives investigating the robberies were able to place Golsby "at the precise location of those six robberies by the GPS device," O'Brien said.

Because the robber's face was covered during the incidents, "absent the GPS device... it would have been hard to pursue those charges," he said.

Golsby is charged with six counts of aggravated robbery and two counts of kidnapping for the attacks in the days before the murder.

Golsby had been wearing an ankle monitor and living in an East Side halfway house since November, when he was released after serving a six-year prison sentence for the attempted rape and robbery of a Grove City woman in 2010.

The Ohio Department of Rehabilitation and Correction, which ordered that Golsby wear the ankle monitor, does not monitor the GPS devices in real time, O'Brien said.

He said records from the halfway house indicated that Golsby had tried to disable the device's battery, "so maybe he thought he had successfully accomplished that."

The 18-count indictment includes death-penalty specifications because Golsby is accused of committing Tokes' murder during the commission of aggravated robbery, kidnapping and rape; killing a person to escape apprehension; and killing a person with prior calculation and design.

O'Brien said Tokes' family supported seeking the death penalty in the case.

Golsby was arrested Feb. 11 after his DNA, in a national database because of his previous conviction, was identified on a cigarette butt found in Tokes' stolen car. He reportedly confessed to the crime and led police to the murder weapon, which had been tossed in a sewer in the Linden area.

O'Brien said it appears that Golsby used the car for about 48 hours before abandoning it on Oakwood Avenue in Columbus not far from where he lived. He is accused of trying to burn the car, which resulted in one of two tampering with evidence charges in the indictment. The other was for hiding the gun.

Tokes was abducted while walking to her 1999 Honda Acura near the intersection of East Third and Mt. Pleasant avenues after finishing her shift at Bodega restaurant. She was forced to withdraw money from an ATM at a bank on South High Street in the German Village area before being raped, shot twice in the head, and dumped at the park, O'Brien said.

A week after his arrest in Tokes' death, Columbus police announced that they were investigating whether Golsby had been involved in recent armed robberies.

According to O'Brien, the robberies occurred Jan. 24 in the 800 block of Bruck Street; Jan. 27 in the 500 block of South 18th Street; Feb. 1 in the 700 block of East Broad Street; Feb. 2 in the 200 block of South Monroe Avenue near Nationwide Children's Hospital; Feb. 6 in the 700 block of Mohawk Street; and Feb. 7 at Carpenter and Newton streets, also near Children's.

The first attack actually occurred Jan. 23, when an intruder repeatedly punched Josie Merkle in the garage of her German Village home. O'Brien said the GPS placed Golsby there at the time, but he wasn't indicted for the incident because no weapon was used and nothing was taken, so only misdemeanor charges would have resulted.

Merkle told The Dispatch that she was upset not to have her case included in the indictment, but happy that the robberies have been solved.

"Everybody is very relieved that he has been associated with the German Village cases," she said.

Golsby is scheduled to be arraigned Monday in Common Pleas Court.

jfutty@dispatch.com

@johnfutty