Howland will forgery trial

The Howland will forgery trial (Robinson v. Mandell) was a U.S. court case in 1868 where businesswoman Henrietta "Hetty" Howland Robinson, who would later become the richest woman in America, contested the validity of the will of her grandaunt, Sylvia Ann Howland.

According to Howland's will, half of her $2 million estate (equivalent to $39,809,000 in 2023) would go to various charities and entities, the rest would be in a trust for Robinson. Robinson challenged the will's validity by producing an earlier will that left the entire estate to Hetty, and which included a clause invalidating any subsequent wills.^{: 68, 81–88, 102} The case was ultimately decided against Robinson after the court ruled that the clause invalidating future wills and Sylvia's signature to it were forgeries.

It is famous for the forensic use of mathematics by Benjamin Peirce as an expert witness.