What shocked Dorothea most of all was the way mentally ill people were treated. Most people who were judged "insane" were locked away in dirty, crowded prison cells. If they misbehaved, they were whipped. Dorothea and other reformers believed that the mentally ill needed treatment and care, not punishment. Massachusetts had one private asylum, or hospital for the mentally ill. But only the wealthy could afford to send a family member there.

For two years she quietly gathered firsthand information about the horrors she had seen, preparing a detailed report for the Massachusetts state legislature. "I come as the advocate of helpless, forgotten, insane and idiotic men and women," she said. "I proceed, gentlemen, briefly call to call your attention to the present state of insane persons, confined...in cages, closets, cellars, stalls and pens! Chained, naked, beaten with rods, and lashed into obedience!" Shocked by her report, lawmakers voted to create public asylums for the mentally ill.