Steven Vondell Williams inadvertently revealed his secret to District detectives when they brought him in for questioning in the shooting death of an H Street delicatessen owner, authorities said in court documents.
Detectives brought Williams, 46, into the police station in August on a warrant for a parole violation, without telling him they wanted to interview him about the slaying of 64-year-old Hae Soon Lim, according to charging documents released Thursday.
Police sat Williams at a detective's desk, where the case jacket for Lim's killing was purposefully left face open.
Williams could not take his eyes off the file, even while a detective asked to take his DNA sample, the charging document said.
Williams refused to give a sample, and the detective left the room. Seconds later, Williams stood up, put on his jacket, hitched his pants and muttered to himself.
"That's a wrap, big boy. That's a wrap, big boy," Williams said to himself.
Williams actions were captured on camera, police say.
He then said, "That's 30 years ... " before his voice trailed off, police say.
On Thursday, a D.C. judge ordered Williams held without bond on a charge of second-degree murder while armed. His preliminary hearing is scheduled for Dec. 17.
The June 14 slaying of the South Korean immigrant was a shock to family and neighbors in Northeast Washington.
Lim, affectionately known as June, was found fatally shot by one of her employees coming to work at the Grace Deli, at Seventh and H streets NE.
Police said Lim was shot in the back of the neck. An empty cash register drawer and empty handgun holster were found next to her body.
Police collected DNA material from the gun holster and submitted it to a national database. In August, the database came back with a match to Williams, police said.
Homicide detectives learned that Williams was wanted for violating his parole for a previous crime and picked him up on the arrest warrant on Aug. 23 and placed him in front of Lim's homicide file.
Williams has been behind bars ever since.
Examiner Staff Writer Naomi Jagoda contributed to this report.