The Alibi of Three

At 12:32, Gang Taejun erased the names on the whiteboard.

Hong Sanguk, Mun Rahui, Yi Juwan. Where the three names had been, he drew three squares of equal size. In the first column he wrote `Central Time`, in the second `Personal Time`, in the third `Action`, and in the fourth `Counterevidence`. The names were pushed down to the bottom left.

"We put the format before the people."

He said.

It was the moment my own timetable turned into an official security team format. It didn't feel good. My method hadn't been endorsed, it had been given a watchdog. Still, that was the right call. A timetable kept alone can be used as an excuse. A shared format, if it's wrong, is wrong together.

Go Yura plugged three cables in under the board. The central log, the collected personal device data, the independent tester. She didn't merge the screens, she put them up side by side.

"If they overlap today too, it's wrong."

"Are you saying that to me."

Gang Taejun asked.

"Today it's for everyone."

Hong Sanguk sat down in front of the first square.

00:07 real time. The central network showed 00:05:57. At that time Hong Sanguk was on the hallway camera in front of the interrogation room. In the footage he never touched the door handle. He tried to call Yi Juwan in front of the door, saw the connection failure notice, and one of Gang Taejun's security team members sat him down in a chair.

Going by central time alone, Hong Sanguk couldn't have pressed R-3. Matching it to personal time made things murkier. The photo of his wristwatch showed 00:06:58, a two second gap from the real time. The wrist was in frame. The fingers were empty.

"Can't you see my hand."

Hong Sanguk asked.

"I can see it."

Gang Taejun answered.

"Then it wasn't a command."

"It's very likely not a direct input. Scheduled execution, delegation, and proxy execution are all still on the table."

Hong Sanguk's lips went tight. The man who had built himself an exit door was now trapped by that same door. Saying he hadn't pressed it himself was no longer enough.

Go Yura wrote two lines in the counterevidence column under Hong Sanguk's name.

`Low likelihood of direct input.`

`Delegation management responsibility remains.`

Hong Sanguk looked at the second line and said.

"The word responsibility is a legal judgment."

Yi Juwan cut in from behind him.

"No. Right now it's a factual judgment. I'll be the one to muddy it into a legal one later."

It didn't sound like a joke. Yi Juwan knew exactly what his role was. Not a man of feeling, but a man who calculated cost. That was why a moment like this was necessary.

The second column was Yi Juwan's.

At central time 00:05:57, he was in front of a terminal in the legal audit office. The terminal had stayed logged in. His personal device received an internal message failure notification at 00:07:01. His face wasn't in the camera. Only his shoulder and right hand showed. The right hand was on a document folder. The left hand had disappeared below the screen's edge.

"This isn't an alibi."

He said it first.

"Why do you say that."

I asked.

"Only my right hand is visible. There's no rule that a remote command has to be pressed with the right hand alone."

He named the point against himself first. That made him more suspicious, not less. A man who treats everything as a transaction lays out even the facts that hurt him like items on a price tag. It could be to trade away something bigger later.

Go Yura opened Yi Juwan's terminal log.

"The central display shows 00:06:44. The real time is 00:07:47. There's a failed attempt to access the authority table from the legal audit office."

"That's after the 00:07 command."

Gang Taejun said.

"Yes, after. So the case for direct command execution is weak. But it does leave the fact that he tried to check the authority table right after the command."

Yi Juwan spread his hands.

"Closer to checking a contract after the fact than issuing a murder command, I suppose."

"Are you going to leave that sentence in the record."

Gang Taejun asked back.

Yi Juwan gave a very brief laugh.

"I won't."

That one line changed the counterevidence column on the board. Low likelihood of direct execution. Possibility of post-hoc confirmation. He didn't drop out of suspicion. Only the location of the crime shifted.

The third column was Mun Rahui's.

She had been in the core antechamber below the control building. The central camera captured her closing a protective cover at 00:05:57. The record from the personal tester showed the same motion at 00:07:00. Whether you corrected for the 63 seconds or not, Mun Rahui was in exactly the same place.

Go Yura's hand stopped.

"That's strange."

Mun Rahui asked right away.

"What's strange about it."

"They both check out."

"It's not strange if the records agree."

"The central network runs 63 seconds slow. The personal tester doesn't run slow at all. And yet your motion matches 00:07 on both standards. One of them should be wrong for this to be normal."

Mun Rahui stared at the screen for a long time. She looked at it a long time, but not like someone flustered. She was calm, like a person before they've corrected a wrong number.

"What about the possibility that I held the same motion for 63 seconds."

"It's possible. That's why we need to check."

Go Yura called up footage from a different angle in the core antechamber. The protective cover closed once. There were 4 seconds between the moment the hand rose and the moment it fell. Not 63 seconds. And yet the central record and the personal record were each perfect by their own standard.

I watched her hands more than her face. Her hands were on her lap. The fingertips didn't move. It wasn't the reaction a scientist gives on seeing a wrong number. She already knew some possibility existed, and she was weighing how far she was allowed to say it.

"It's a synchronization marker."

She said.

"Explain."

Gang Taejun's words grew short.

"The core antechamber camera films the central network display and the personal tester's auxiliary marker together in the same shot. The number on the left of the screen is the central standard, and the small flicker on the right is the independent standard. It's possible that in the edited version, the two were arranged to look like the same number."

"Who edited it."

"That can't be known from this material alone."

Saying it couldn't be known was useful. It wasn't an omniscient explanation. Mun Rahui added nothing that could build her own innocence. That made her more dangerous, not less.

Go Yura broke the footage down into raw frames. The central number read 00:05:57. The independent flicker read a 00:07 signal. Both were inside the same frame. No one had edited it, the footage itself was structured to show two times at once.

"Then Doctor Mun Rahui's alibi matches both standards."

I said.

Gang Taejun drew the line right away.

"We don't write someone down as the killer because they're too perfect."

He wrote in the counterevidence column on the board.

`Direct input unknown. Presence in core antechamber confirmed. Matches 00:07 on both standards.`

Mun Rahui didn't correct the sentence. Instead she looked toward me.

"Why do you keep looking at that column, Seo Ihyeon."

"Data that checks out on both sides is usually hiding one of them."

"Are you concluding it's hiding something."

"Not yet."

She nodded. It wasn't the nod of someone who had given the answer. It was the nod of someone permitting the scope of the inspection.

At 13:12, Gang Taejun called my timetable back up in its official format.

At the top of the page he wrote `Investigation Timetable A-00:07`. Author, Gang Taejun. Technical verification, Go Yura. First observer, Seo Ihyeon. My name wasn't at the front. I felt like I didn't like the order, and then set the feeling aside. If the first observer becomes the author, then even my own mistakes become my own defense.

Gang Taejun put the same questions to the three of them in the same order.

"What you were doing at real time 00:07."

"An independent record proving that action."

"The hand with no record."

Hong Sanguk stopped for the first time at the third question.

"What do you mean, the hand with no record."

"An action not visible on camera."

"There isn't one."

"That's recorded as a statement, not as proof of absence."

Hong Sanguk's statement column filled in with `Claims no action outside camera view.` He disliked that sentence. The word claim lowers even a director's words to the same level as anyone else's.

Yi Juwan answered the third question faster.

"My left hand was below the frame. That works against me."

"What could you have done."

"Operating my personal terminal was possible. But scheduling the R-3 execution was impossible under my personal authority."

"Did you know the delegation account."

"I knew the account group existed. I'd like to say I don't know the specific keys, but I don't rule out the possibility that I did know."

That wouldn't be a defense in court. In an investigation it was useful. He didn't build a safe sentence out of a lie. Instead he worked out and presented the margin within which he could still slip free.

When asked about the hand with no record, Mun Rahui showed her own wrists.

"Both hands are in the footage."

"Who confirms that."

"It should be confirmed by the footage, not by me."

Go Yura zoomed in on the frame. The right hand was over the protective cover, the left hand was on the antechamber railing. That was true for 4 seconds. But if R-3 was a scheduled command, the hand alone at that instant of 00:07 wasn't enough.

Gang Taejun added a fourth question because of that.

"Could you have created the schedule before 00:07."

None of the three could answer that question right away. An alibi shows the hand in the present. A schedule demands the hand in the past. The board had gotten more complicated, but it had also gotten fairer.

At 13:35, we read through the three columns again.

Hong Sanguk had difficulty with direct input, but delegation responsibility remained. Yi Juwan had tried to check the authority table after the command. Mun Rahui had been in a place that matched both time standards. All three were possible, and all three fell short. The single killer hypothesis for Oh Sejin grew weaker still. He had been the first hand. The second hand moved by different rules.

Yun Haewon saw that her own name was missing from the board.

"Aren't you going to ask about my alibi."

Gang Taejun answered.

"The victim isn't excluded from this scope. But we don't put the candidates for executing the 00:07 command and the responsibility for the envelope's design in the same column."

Yun Haewon didn't laugh at that.

"That's fair. And uncomfortable."

"It should be uncomfortable."

I wrote that exchange down in the ledger. A format uncomfortable even for the victim. That way it would come for me too.

Go Yura didn't take a photo of the board at the end. Instead she sealed the table file with a hash. A photo is convenient, a hash is tedious. Tedious things betray you less later.

"Next we need a scene reenactment."

She said.

"Which scene."

The restaurant. The black glass at 08:12. Doctor Oh Sejin's alibi needs to be fixed down again with that. If we only look at 00:07, the second hand gets too big. The first hand needs to be pinned down exactly too.

Gang Taejun nodded. My timetable had become an official format, and Go Yura's log had set the next move. The investigation wasn't riding on one person's talent. That was a small relief, and a small discomfort.

Only Mun Rahui's column stayed on the board, unerased.

An alibi that checked out before correction, and checked out after correction too.

Gang Taejun drew a new line underneath it.

`Perfection is not evidence. But it is a subject for verification.`

Below that line he attached three copies of the timetable. Hong Sanguk's led to delegation responsibility. Yi Juwan's led to a post-hoc check of the authority table. Mun Rahui's led nowhere at all. An alibi that leads nowhere isn't safe, it's a record that hasn't found its connection point yet.

Go Yura put a small mark next to Mun Rahui's column. `Holds both before and after the 63 second correction.` Mun Rahui didn't ask her to erase the mark. Not erasing it isn't proof of innocence. But it wasn't an act of concealment either. That was why it stayed longer.

I looked at the three names again. Hong Sanguk remained defined by authority, Yi Juwan by documents, Mun Rahui by time. All three candidates seemed possible, and all three still fell short. If this was a fair narrowing down, fairness was slower than an answer.

Gang Taejun left Oh Sejin's name small at the bottom of the board, last of all. He hadn't erased it. The first hand had already been captured, and the current table was the range of the second hand. Because Oh Sejin had been placed below, the three candidates couldn't cover up his guilt. An investigation isn't about removing people, it's about placing them in a different column within the same case.

In the bottom right corner of the copy he wrote `Weakened, the single killer hypothesis for Oh Sejin.` Weakened is not innocent. That one word preserved the first hand and the second hand at the same time.

Mun Rahui read that line and said nothing at all. A perfect alibi still wasn't proof of a killer. But among the three, only her column hadn't changed shape, even after 63 seconds had passed.