A No-Contact Order He Never Lived to Enforce: The Murder of Hartanto Santoso

Author

Benjamin Hayes

Publication Date

April 20, 2026

Hartanto Teguh Santoso was born May 8, 1969, an Indonesian national who went by the nicknames Toto, Marko, and Santos among the people who knew him. By February 2001 he was thirty one years old, working as a nursing assistant and living at the Four Cedars Apartments in Kirkland, Washington, a city on the eastern shore of Lake Washington across from Seattle. Santoso was HIV positive, and at some point had become involved in a sexual relationship with a professional kickboxer named Kim Heichel Mason, a relationship that would end up costing Santoso his life.

An Assault He Reported Before He Disappeared

About three weeks before he vanished, Santoso experienced a terrifying assault at Mason's hands, one serious enough that he went to police and filed a formal complaint. According to that complaint, Mason had choked him into unconsciousness, bound him with duct tape, and threatened him with both a gun and a syringe filled with drain cleaner, forcing him at one point to write out a check for seven hundred dollars. Santoso obtained a no contact order against Mason as a result, and the case moved forward toward an assault trial in which Santoso was scheduled to serve as the key witness testifying against the man who had attacked him. He never got the chance.

Screams, Breaking Glass, and a Car Speeding Away

On the evening of February 19, 2001, neighbors at the Four Cedars Apartments heard breaking glass, banging, thumping, and several distinct screams coming from Santoso's unit around 10:45 p.m., followed shortly after by the sound of a car speeding away around eleven o'clock. When police responded, they found Santoso's front door standing open, a cinder block that had been thrown through a window, and a considerable amount of blood inside the residence alongside signs that the apartment had been ransacked in what looked like a staged burglary. Santoso himself was gone. His dark green 1999 Ford Mustang convertible was later located at Seattle-Tacoma International Airport, seemingly positioned there deliberately to suggest he had simply left the country, though the substantial amount of Santoso's blood found mixed inside the car told an entirely different story. A knife covered in his blood turned up separately in Newcastle, Washington, discarded near Interstate 405.

A Case Built on Four Hundred Pieces of Evidence

Kim Mason was arrested and initially charged with first degree kidnapping and robbery, charges that were upgraded to first degree murder by April 2001 as investigators built out the case against him. When the matter finally went to trial in the spring of 2003, prosecutors presented an unusually extensive body of evidence for a case with no recovered body, introducing roughly four hundred separate exhibits and calling close to seventy witnesses over the course of the proceedings. Their central theory held that Mason had broken into Santoso's apartment that February night, slit his throat, and stabbed him to death, then staged the scene to look like a burglary before moving the body and driving Santoso's own car to the airport specifically to create the impression that he had voluntarily left the country rather than been murdered.

The most damning physical evidence came from DNA testing, which found Mason's own blood mixed together with Santoso's, not only inside Santoso's Mustang but also inside a separate vehicle belonging to Marina Madrid, Mason's ex-girlfriend. Madrid herself became the prosecution's central witness, testifying under a grant of immunity after admitting she had helped Mason cover up what he'd done. According to her account, Mason picked her up from the airport that same night with a bandaged thigh, telling her flatly that Santos is no longer a problem. She testified that Mason disappeared again for three days afterward, and that when he finally returned, he told her he had gone back specifically to decapitate Santoso's body, reasoning that removing the head would make identifying the remains, if they were ever found, considerably more difficult. Notably, despite this overwhelming circumstantial and forensic case, investigators were never able to find Mason's own fingerprints anywhere inside Santoso's apartment, a detail his defense leaned on without ultimately swaying the jury.

A Conviction in Under Six Hours

The King County jury took less than six hours to reach a verdict in June 2003, convicting Kim Mason of aggravated first degree murder, finding specifically that he had killed Santoso during the course of a burglary and in direct violation of the no contact order Santoso had obtained against him weeks earlier. Because Washington law treats aggravated first degree murder as carrying an automatic sentence, Mason received life in prison without the possibility of parole the moment the conviction was entered. He has maintained his innocence in the years since, and Santoso's body has never been recovered, despite the case producing enough physical and testimonial evidence to secure a conviction that has held for over two decades.

A Six Figure Investigation for a Body Never Found

The scale of the investigation into Santoso's disappearance and presumed murder became its own point of local interest years after Mason's conviction, when reporting revealed that the case had ultimately cost Kirkland area law enforcement more than two hundred thousand dollars to investigate and prosecute, an extraordinary sum for a case that, in the end, still never produced a body for Santoso's family to recover or bury. That figure reflects just how extensively investigators had to work to build a homicide case from a scene that had been deliberately staged to look like something else entirely, a burglary and a voluntary disappearance rather than the calculated killing of a man who had already gone to police once, seeking protection from exactly the person who would go on to kill him anyway. Detectives spent years chasing down forensic testing on the recovered knife, tracing Mason's movements during the three days he was unaccounted for after the killing, and corroborating Marina Madrid's account against the physical evidence recovered from both vehicles, work that ultimately produced one of the more expensive homicide investigations King County had handled up to that point precisely because there was no crime scene in the traditional sense, only a ransacked apartment, a bloodied car left at an airport, and a knife discarded miles away along a highway.

Justice Without a Body

More than two decades after Hartanto Santoso disappeared from his Kirkland apartment, his case remains one of Washington State's more thoroughly documented examples of a murder conviction secured entirely without physical remains, built instead on blood evidence, a cooperating witness's testimony, and the grim specificity of a confession describing decapitation as a deliberate act of concealment. Santoso had done everything the legal system typically asks of a victim of violence, reporting the assault, obtaining a protective order, and preparing to testify against his attacker in court. None of it was enough to save him, though it did, ultimately, help convict the man responsible, even without ever recovering the one piece of evidence, Santoso himself, that might have finally given his case a true ending.

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