A gunman pulled up alongside them and opened fire. Jazmine’s mother, LaPorsha Washington, 30, was injured. Ms. Washington and her daughters met with investigators to help them create a composite sketch of the gunman, who attacked them before sunrise.

The man was described as white, thin and in his 30s or 40s and driving a red pickup truck. On Sunday, the authorities announced they had charged a 20-year-old black man with capital murder in connection with the shooting. In a CNN interview, Ms. Washington said her teenage daughter told her that the man was white and that his hoodie was black.

“That’s all she could see at the time because the sun hadn’t really even came out yet,” Ms. Washington said in the interview.

For days, the search for a white man dominated news headlines. The unexpected turn — that the suspect charged was black and not white — was not intentional, Sheriff Ed Gonzalez of Harris County, Tex., said at a news conference on Sunday. The person driving the pickup, who the police now believe was likely a witness to the shooting, might have been the last thing Jazmine’s family remembered “prior to the mayhem and chaos,” the sheriff said.

Lori Brown, a criminologist at Meredith College in Raleigh, N.C., said “eyewitness testimony is the least reliable evidence you can have” because people try to understand how a traumatic event could have happened by using what they know about the world. “Unfortunately,” she said, “we fill in the gaps.”