A little more than a week after the murder, Stephen White received a letter from a jailer 70 miles away in New Bedford. The letter said an inmate named Hatch, a petty thief, claimed he had crucial information. While frequenting gambling houses in February, Hatch had overheard two brothers, Richard and George Crowninshield, discussing their intent to steal Joseph White’s iron chest. The Crowninshield brothers were the disreputable scions of an eminent Salem family. Richard, according to court transcripts, was known to favor Salem’s “haunts of vice.” The town’s Committee of Vigilance brought Hatch in chains to testify before a Salem grand jury. On May 5, 1830, the jury indicted Richard Crowninshield for murder. His brother George—and two other men who were in his company at the gambling house—were charged with abetting the crime. All were detained in the Salem Gaol, a grim edifice of granite blocks, iron-barred windows and brick-walled cells.
Then, on May 14, Joseph Knapp Sr., the father of the man who had married White’s disinherited grandniece, received a letter from Belfast, Maine. It demanded a “loan” of $350, and threatened disclosure and ruin if this were not promptly paid. It was signed “Charles Grant.”
The senior Knapp could make no sense of the matter and asked his son for advice. It’s “a devilish lot of trash,” Joe Knapp Jr. told his father and advised him to give it to the committee.
The Committee of Vigilance pounced on the letter. It sent $50 anonymously to Grant at his local post office, with a promise of more to come, and a man was dispatched to apprehend whoever collected the money. The recipient turned out to be John C.R. Palmer. Arrested as a possible accessory to the murder, but promised immunity for his testimony, he told a complex tale: during a stay at the Crowninshield family home, Palmer had overheard George tell Richard that John Francis (“Frank”) Knapp, a son of Joseph Knapp Sr., wanted them to kill Captain White—and that Joe Jr., Frank’s brother, would pay them $1,000 to commit the crime. The Committee of Vigilance promptly arrested the Knapp brothers and sent them to the Salem Gaol, their cells not far from those occupied by the Crowninshields.
At first, Richard Crowninshield exuded a sense of rectitude, certain that he would be found innocent. During his imprisonment, he asked for books on mathematics and Cicero’s Orations, and conveyed nonchalance—until the end of May, when Joe Knapp confessed to his role in the murder plot.
The confession was given to the Rev. Henry Colman, an intimate friend of the White family. Colman also had close connections to the Committee of Vigilance, and in this role had promised Joe immunity from prosecution in exchange for his testimony.
The nine-page confession—in Colman’s handwriting but signed by Knapp—began, “I mentioned to my brother John Francis Knapp, in February last, that I would not begrudge one thousand dollars that the old gentleman, meaning Capt. Joseph White of Salem, was dead.” It went on to explain that Joe Knapp believed if Captain White died without a legal will, his fortune would be divided among his close relatives, giving Mary Beckford, Knapp’s mother-in-law, a considerable fortune.
To this end, Joe opened Captain White’s iron chest four days before the murder and stole what he erroneously believed to be the old man’s legal will. The true last will of Joseph White, favoring his nephew Stephen, was safely in the office of the dead man’s lawyer. But Joe was unaware of this fact. He hid the document in a box he covered with hay and burned the stolen paper the day after the murder.
Joe and Frank had debated how to commit the murder. They considered ambushing White on a road or attacking him in his house. Frank, however, told Joe that “he had not the pluck to do it,” and suggested hiring Richard and George Crowninshield, whom the Knapp brothers had known since adolescence.
After several meetings, the Knapps and the Crowninshields gathered at the Salem Common at 8 p.m. on April 2 to finalize the plan. Richard, Joe confessed, had thoughtfully displayed the “tools” he planned to use for the project. Using his machinist’s skills, he had manufactured one of the murder weapons—a club—himself. It was “two feet long, turned of hard wood...and ornamented...with beads at the end to keep it from slipping....The dirk was about five inches long on the blade...sharp at both edges, and tapering to a point.”