Shahidullah Shahid said Malala was shot because she was used in anti-Taliban propaganda, and would be targeted again just as anyone who opposes the militants would be.
Shahid denied promoting education for girls was behind the 2012 assassination attempt.
Malala was 15 when gunmen attacked her school bus in Pakistan's Swat Valley Oct. 9, 2012, and shot her in the head. She underwent brain surgery in Britain, recovered and addressed the United Nations in New York on her 16th birthday in July.
The Taliban shooting of the girl brought worldwide condemnation.
The Taliban banned girls from schools in the Swat Valley in 2009. Malala anonymously blogged for the BBC in opposition to the Taliban order and became an advocate for girls' education.
This year, the Malala Fund was created to support education for girls worldwide. She has been mentioned as a possible recipient of the Nobel Peace Prize, which is to be announced Friday.
"In some parts of the world, students are going to school every day. It's their normal life," Malala told ABC News in an exclusive interview. "But in other parts of the world, we are starving for education ... it's like a precious gift. It's like a diamond."
Even though she knew threats had been made against her, she said she never expected the Taliban to harm a young girl, Malala told ABC News.
"It was always my desire before the attack that if a man comes ... I would tell that man that education is very important," Malala said. "I will tell that man that I even want education for your daughter."
Malala said, "I thought that words and books and pens are more powerful than guns."
Her memoir, "I am Malala," will be published Tuesday. On Oct. 18, she is expected attend a "Youth, Education and the Commonwealth" reception hosted by Queen Elizabeth II.
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