Bigger encourages the police and the Daltons to think that jan is involved in Mary's disappearance by signing the document Red.
How Bigger encouraged the police
In Richard Wright's "Native Son," Bigger's signing of the ransom note "Red" is a vital moment that encourages suspicion towards Jan and fuels the search for Mary.
Mary Dalton, the daughter of Bigger's employer, had vanished, and suspicion falls upon Bigger due to their tense interactions and his previous involvement with Bessie, another worker in the Dalton household. Bigger, desperate, and cornered, writes a ransom note demanding $10,000 for Mary's return. He signs it "Red". This is a reference to a Communist pamphlet he once read.