Journalists are sometimes accused of giving disproportionate attention to crimes against their own. The reason they do so is not self-aggrandizement; it is that the increasingly frequent murder or repression of reporters is rarely random, and most often it is the work of people in power seeking to extinguish an unwelcome light on their corruption. To report on the fate of silenced journalists is to continue their work.

Daphne Caruana Galizia was such a reporter. When she was blown up by a car bomb in October 2017 in the tiny Mediterranean country of Malta, population roughly 450,000, the prime minister, Joseph Muscat, acknowledged that the list of potential suspects — people who had been scorched by her fearless reporting — was very long. At the time she was killed, Ms. Caruana Galizia was reporting on mysterious offshore companies that she said were linked to Maltese politicians.

Three men were soon arrested. But they were accused of being the contract killers, hired to kill the 53-year-old blogger for about $165,000, and with time it came to seem that the real masterminds of the murder would never be revealed.

That changed with the chance arrest of a suspected middleman who offered information about Ms. Caruana Galizia’s murder in exchange for immunity. Last week, one of Malta’s most prominent businessmen — and a prominent subject of Ms. Caruana Galizia’s reporting — was arrested as he was trying to leave his yacht. He in turn offered to testify against two senior government officials and others “close to the prime minister” in exchange for a pardon.