Prosenjit Chatterjee is happy that his film, Force, directed by Raja Chanda has been declared tax free. ���I feel the film deals with a serious problem like autism, which affects millions of children. It has a strong message to convey and shows how to deal with autistic children through love and affection. So, I requested the government to declare it tax free and was overjoyed when the letter granting this reached my office on Monday night,��� he said.