in tonight's signature segment, special correspondent alison stewart went to texas to see how that law is working. >> i grew up with him from a baby. and i adored him. he was kind of eccentric. he had his flaws. but, oh my god, he was a good man. >> reporter: sonia cacy is describing her uncle, bill richardson. in the early 1990s, cacy lived in fort stockton, texas with her uncle, who was in his seventies and suffering from a form of dementia. on the morning of november 10th, 1991, everything changed. >> the night before we watched a movie together. burt lancaster was in it, and that was my favorite. and then when that was over, it was a late movie, i went to bed, and we were both alive. >> reporter: around dawn, a fire broke out in their home. the then 44 year old cacy escaped through a window and ran to a neighbor, who called 911. when emergency responders found richardson, the 76-year-old man was dead. authorities said the fire was suspicious. when did you sense, sonia, that the authorities suspected you of setting the fire? >> well, they took me to the hospital. i was there eight d