In the letter, published in The Hollywood Reporter, the Crash director writes, "I can't express how much I admire Leah. Her parents, family and close friends were almost all Scientologists; the stakes for her were so much higher than for me. Her decision to leave was so much braver."
Remini, who is a second-generation Scientologist, fell out of favor with the church after challenging the leadership of highest-ranking member David Miscavige and questioning the whereabouts of Miscavige's wife, Shelly, who has not been seen in public since 2005.
Like Remini, Haggis publicly criticized Scientology's policy of having members isolate themselves from their family members and loved ones who are not involved in the church. He describes Remini as "one of two Scientologists who had refused to 'disconnect' from me and certainly the only high-profile one when I decided to quit the organization in August 2009."
Haggis says he learned that Remini was subsequently reprimanded by church officials for keeping in contact with Haggis and defending him to other members.
"The fact that she fought within the system so resolutely for so long, never making her feelings public, is a testament to how much she believed in the basic goodness of her friends and the institution," Haggis writes. "According to what I read, she was turned in by a celebrity friend who had noticed one of our few innocuous tweets."
In response to Haggis' letter, the Church of Scientology released a statement Wednesday that claimed he's a "status-obsessed screenwriter," described his remarks as "delusional" and "border[ing] on paranoia," and called the letter "a transparent plug for an upcoming film still lacking U.S. distribution."
"Paul Haggis has no first-hand knowledge about the Church of Scientology but instead relies on a small collection of unemployed bloggers living on the fringe of the Internet who are obsessed with spinning myths about the Church," the statement reads in part. "Mr. Haggis has chosen to align himself with a small posse of lunatics with arrest records, who have acknowledged in depositions to being secretly on the payroll of tabloids and who have admitted on national television to outright lying."
Haggis says he reached out to Remini in the wake of her announcement. "It was good to hear her voice and great to hear her laugh — though it was easy to tell she had been terribly hurt and shaken by the events of the last weeks," he writes. "That said, Leah is an incredibly strong woman and will get through this with the help of her family and her true friends."