Johana Márquez Murder becomes a pivotal case because Jasón Medina’s confession seemed to settle responsibility for her death, yet evidence associated with the crime suggested that another person may have been involved. The distinction between Medina’s admitted actions and the unexplained features of the case opened a wider investigation into linked murders.

Causes and Background

Johana was Medina’s stepdaughter. After he was arrested, he confessed to killing her and described trying to imitate a crime attributed to the Basajaun, which he had read about in the press. Amaia Salazar regarded his responsibility for the murder as established, but the case did not end with his confession: investigators were also confronting evidence of an arm’s-length amputation and remains found at Arri Zahar, details that prompted Teniente Padua to seek her help in assessing possible connections.

Evidence Linking the Cases

The comparison widened when investigators set Johana’s case beside the killing of Lucía Aguirre in Lekaroz a year earlier. Both victims had the same distinctive injury: a forearm had been removed at the elbow. The men convicted of their deaths also died by suicide, leaving messages that investigators judged strikingly similar. In the inquiry, those correspondences complicated the apparent finality of Medina’s confession and raised the possibility that the acts associated with the two cases did not all belong to the same offender.

The details of Medina’s confession sharpened that distinction. He had admitted killing Johana and said he later returned to obtain a rope so he could imitate a crime attributed to the Basajaun, as reported in the press. But he appeared unable to explain the missing arm: after he returned, Johana’s arm was already gone. Investigators also noted that the detailed information about the amputation had been withheld from the public, making an imitation based on press coverage less plausible. A forensic description characterized the removal as having been made with a toothed but sharp implement, such as an electric knife or jigsaw; investigators treated the repeated feature as a possible signature rather than simply part of Medina’s admitted conduct.

The Unresolved Signature

The investigation also tested whether Medina fit the pattern investigators were assembling. Amaia Salazar noted that he lacked the aggressive or intensely frustrated profile associated with the other men under comparison. His wife’s suspicions had instead centered on his troubling attention to Johana and his increasingly close scrutiny of the girl’s schedule, outings, and clothing. Those observations explained why he had come under suspicion, but they did not account for the unexplained feature that distinguished the case.

The inquiry widened beyond Johana and Lucía Aguirre when investigators found two more women born in the Baztán Valley who had been killed by their partners. One had lived in Bilbao and the other in Burgos; notices for both had appeared at funeral homes in the valley. Their cases added a victim-based line of comparison, but the evidence presented them as leads for further investigation, not as proof that all the deaths shared a perpetrator.

The central uncertainty remained the apparent divide between Medina’s admitted crime and the repeated, unexplained signature. Investigators considered it unlikely that the detailed amputation method had been copied from press reports, since that information had been withheld from the public. They also questioned how an unplanned crime could coincide with the arrival of a figure they called Tarttalo, who took the trophy. The case therefore remained significant not only for what Medina confessed, but for the possibility that his confession described only part of what had happened.

The Cell Inscriptions

The inscriptions supplied a more exact comparison than the general resemblance between the cases: the message left by the Logroño murderer was written on his cell wall in the same distinctive handwriting as the message left by Jasón Medina, and with an unusual spelling that doubled a letter where the common form used only one. Quiralte, meanwhile, had described scratching a nonsensical mark into the plaster with the handle of his toothbrush. Taken together, the wall writing and Medina’s note made the repeated wording look less like a detail borrowed from public reporting and more like a trace connecting separate crimes.