"A Feat of Deceitful Legal Alchemy"

"Field nonetheless saw Davis's erroneous summary as an opportunity. A few years later, in an opinion in an unrelated case, Field wrote that 'corporations are persons within the meaning' of the Fourteenth Amendment. 'It was so held in Santa Clara County v. Southern Pacific Railroad,' explained Field, who knew very well that the Court had done no such thing.
"His gambit worked. In the following years, the case would be cited over and over by courts across the nation, including the Supreme Court, for deciding that corporations had rights under the Fourteenth Amendment."

Adam Winkler at The Atlantic explains how corporations became "people."