"Got a live one, Sarge," Russell told me. King was dressed all in black, with a black watch cap covering sparse blond hair. He'd smeared his pudgy face with some sort of dark makeup. Even so, his clothes were new and the Rolex on his wrist made it clear he wasn't a street thug.

"Sergeant," King said, struggling to break free from Bell, "I want to report a murder. Someone killed my wife."

"Yeah, asshole," Russell said, yanking on his cuffs. "You did."

"We found him locked in his ex-wife's apartment, Sarge," Bell said, holding the squirming King with ease. "No prints on the gun, but it's registered to him. The crime scene techs are going through her security camera footage."

"I'm innocent!" King shouted as Bell dragged him back into the squad room for interrogation. I yawned and logged the arrest.

No one else was in the interrogation room. Sophia Weiss and her partner, Virgil Goodenough, were out on a call for a body in a red suit. In a fireplace. I hoped I didn't have to be part of booking an elf as a suspect. I'd never live it down.

After about ten minutes Russell came out into the lobby, slamming the door hard enough to break hinges. She stalked around my desk muttering ferocious curses that ionized the air.

"Russell," I said, "you need to calm down. What's going on?"

She stopped in front of the desk and stood, rocking on the balls of her feet. "That son of a bitch just killed his wife, and he wants me to feel sorry for him!" she exploded.

"Don't they all?" I asked. "Why's this one getting under your skin?"

"Men!" she exclaimed. Then she saw me scowl. I'd had enough of my ex-wife's lawyer hating on me.

"Oh, not you Sarge! Just this jerk. He thinks he should get to kill her because he's got one of these blockchain marriage contracts. Thinks it's unfair he can't get out of it without giving her most of his money."

"What's a block and chain contract?" I asked her. "Some kind of new prenuptial?"

"Nah, it's one of those new super secure marriage contracts."

"Tell me about it," I said. "I'm Catholic. I haven't lived with my wife the last four years and we're still waiting for an annulment. Which they will only grant if Kathy proves what a monster I am. I know all about secure marriage contracts."

Russell looked puzzled, then her eyes went wide. I could almost see the light bulb glowing over her head.

"No, not that, Sarge. The blockchain part is the security. This blockchain marriage contract is self-executing."

"I'm not sure that makes more sense. How's it work?"

Her constant motion slowed down a bit. "Well, if a regular contract says you'll do something, like buy a house, someone has to enforce it. If you don't do what you promised, they need to make you. Maybe by messing with your credit rating or suing you."

"Yeah," I said, "I get it. My wife's divorce lawyer is ruining my credit."

"A blockchain contract isn't just secure, it's self-executing. If you don't close on your house, the contract does it for you. It transfers money from your account to the seller's account and records the deal with the state."

"What's this got to do with divorce?" I asked.

She relaxed into her explanation, quit bouncing entirely. "If he files for divorce, this contract transfers half his funds to her. Then it sets up monthly alimony payments. He can't use a sharp lawyer to keep her from getting his money."

"How does a piece of paper, excuse me, a digital contract, do anything. How can it close on a mortgage or transfer money from one bank account to another?"

"Some sort of digital bank does it," she replied. "Computers already do most stuff at banks anyway. Bankers don't do anything but watch." Her expression soured. "Ask my brother."

"Computers!" I swore, scratching my head in confusion. "I still don't get how killing her can help."

"That's where this guy went off the rails," she said with a smug grin. "The contract has a clause that says if the ME files a death certificate on her, the contract cancels itself. It disappears. He keeps all his money."

"Didn't it occur to him we might figure out who killed her?"

"I think he was planning to be in Brazil when it happened and didn't plan to come back."

It was my turn to smile. "Kind of hard to kill her from Brazil."

"Well," she said, smiling like a cat playing with a mouse, "he didn't plan to kill her himself. He hired someone else to do it."

"This isn't making sense," I said, turning away from her to return to playing solitaire on my computer.

"No, listen, Sarge," she said, grabbing my sleeve. "The murder was supposed to happen last week. The killer didn't follow through. King came back from Brazil under a false passport to do the job himself."

"What went wrong?"

"He got into her apartment with his own key and shot her. He wasn't counting on her automated security system. It was monitoring her vital signs. When she died, the system went into full lockdown mode. Doors, windows, even the rooftop access locked up tight. Then the apartment called 911. He was planning to toss the place to make it look like a robbery, get out, go back to Brazil and be home free. Instead the apartment arrested him." She chortled at her own joke.

"Don't tell me," I said. "The security system was under a block and tackle contract."

"Blockchain, Sarge, but you got it right."

The door buzzer sounded, and I checked the video monitor. Jerry Wetzel, my favorite scumbag defense attorney, was in the vestibule. I buzzed him in and he walked into the anteroom, kicking snow off his tasseled loafers.

"I understand you've got my client under arrest for murder," Jerry said, suppressing a yawn. "I need to talk to him."

I looked at Russell. She frowned but waved for him to follow her back to interrogation. I went back to solitaire.

Ten minutes later Jerry Wetzel walked back into the squad room with Russell. Bell was nowhere to be seen.

"Sergeant," said Wetzel, "According to Detective Bell, Mr. King's arraignment will happen the day after Christmas. I'd like you to make a notation in your log that Mr. King says he's innocent of this crime."

"Sure, Counselor," I said. Suspect's lawyer says he's innocent. Film at eleven. Hot news.

Russell walked Wetzel to the door, and he disappeared into the night. She went back to process King and I went back to the computer. Nothing else happened that shift. No one arrested an elf. Thank God.

Christmas Day dawned, and I headed home. Eight hours later I woke up, made coffee, turned on my Christmas tree and sat down at the kitchen table. I turned on the news before making myself something to eat.

"... was gunned down on the steps of the courthouse," CNN blared. "Judge Robert Wainwright presided over an emergency Christmas Day arraignment that released King into the custody of his attorney, Jerry Wetzel. As Mr. Wetzel and Mr. King left the courthouse, before Mr. King had descended halfway to the street a shot from a building across the street killed the defendant where he stood. Police are searching for a sniper, but no arrests have been made."

What the hell? I got out of my chair, crossed the room and dialed the precinct.

"Seventeenth Precinct, Sergeant Washington speaking."

"Joe, it's Vince," I said. "I just saw the news about Jeffrey King. He was arrested last night at 2 AM. How the hell did he get a judge away from his family on Christmas Day? And how could a shooter be ready for his release? Something's fishy."

"Jackie Russell came in to handle the case," Washington said. "Let me transfer you to her."

The phone rang four times before she picked up. "Detective Russell."

"Jackie, it's Vince Decorsi. What the hell happened with your murder case?"

"You got me, Sarge," she said. "The DA called me this morning to ask about King and the case. I told her he as much as confessed. Why she went along with his release I'll never know."

"Judge Wainwright used to be Wetzel's law partner." I said. "Coming in on Christmas Day for an 'emergency' hearing sounds like a favor for a friend."

"He didn't do King any favors," Russell said with an audible yawn.

"Let's focus on Wetzel. Not much we can do about the judge ruining his own Christmas."

"You know what's odd, Sarge? ," Russell said. "Jerry Wetzel was the vic's attorney before she married King. He was the one who drew up the blockchain marriage contract."

"If I had just killed my wife, I sure wouldn't call her lawyer to bail me out of jail," I told her.

"Me, either," she laughed. "Maybe the contract called him. I'd better let you go, Sarge. Ken and I caught the sniper case as well. This is the last time I volunteer for Christmas duty. I'd rather have Christmas dinner with my mother and worthless brother."

"I hear ya," I said, and hung up.

Two nights later, I was on the desk again when Bell and Russell came in from a crime scene. From what the dispatcher told me, it was a drug murder likely to put a dent in our closure stats for the year. None of the witnesses would admit to seeing anything. Not that they remembered there had been a shooting at all.

Russell veered off from the other two and came to my desk.

"Sarge," she said, "you're not going to believe what we found out about the King murders."

"Try me," I said. Whatever she had to say, it would be less boring than riding the desk.

"I pulled up a copy of the blockchain contract. It had a picture of the bride and groom at the wedding right on page 1. Ken and I thought that was unusual, so we asked our IT consultant to take a look. You ever hear of steganography, Sarge?"

"Those dinosaurs with the triangles on their spine?" I asked.

Jackie's face froze up like it might when your kid said something endearingly dumb and you didn't want to hurt her feelings.

"That's stegosaurus, Sarge," she said, speaking slowly. "Steganography is a way to encode words inside a chunk of data, like a picture. Turns out there was a special clause hiding in the wedding picture."

"Special clause?" I couldn't see the point of being offended by her drawn-out spiel, I might learn something if I listened.

"The clause specified if the wife was murdered and the husband was accused, a substantial payment would be transferred to a company called of Acme Pest Control. Maybe it's cover for a hit squad."

"How can you enforce a contract clause the person who signed it didn't know it was there."

"The computer did it, Sarge. ." She tried to suppress a laugh. "I ain't no lawyer. Maybe somebody can sue the company that owns the computer. Not much help for King down in the morgue."

"So, Acme Pest Control? Ever heard of it?"

"Not me, Sarge. Bell's checking it out. Wetzel has some pretty shady clients with ties to the Russian mob. Maybe they're behind Acme."

"Did King actually sign the contract?"

"He did."

"Who'd be dumb enough to do that?"

"Someone who'd be dumb enough to let his wife's lawyer draw up a blockchain marriage contract."

"Maybe he didn't know Wetzel was her lawyer. He struck me as kind of impulsive."

"The best part, Sarge, Wetzel was her ex-boyfriend. Bell questioned the first Mrs. King. She said Wetzel wasn't happy when the late Mrs. King decided to marry our vic. I guess a tech entrepreneur has way more money than a divorce attorney."

"Both of whom have more money than either one of us. What have you got on the sniper case?"

"The damn sniper's a ghost. We found his, or her, nest, but no brass, no prints, no half-eaten chicken leg, nothing. No way we're finding this one."

"Whoever pulled the trigger, I'd be looking for the lawyer. Not only did he draft the contract with the picture, he had a grudge against King."

"Wetzel left for Venezuela the day after Christmas, Sarge. We're trying to contact him, but if he's implicated there's no way he's going to cooperate. Looks like another unsolved case for our stats. I'm about ready to go shoot Bell, just so I can arrest myself and clear one more case."

"So who gets the money now?"

"Damfino," Russell said and headed back to her own desk.

What a world. Blockchains, steganography. I know about putting out contracts on people. Now a contract had one of the parties killed based on a clause he didn't even know was in it. These days the old ball and chain came with an unbreakable lock. Somehow a Catholic marriage, with even a slim chance of an annulment, sounded like freedom itself. At least, I was pretty sure Kathy wasn't going to put out a hit on me.