 On the other hand, at Carleton University, driving decreased by 33%.This raised some doubts at the University of Ottawa as to the environmental and social benefits of the U-Pass, considering that walking and cycling produces no pollution, whereas bus use causes pollution.Some students at University of Ottawa have taken their student union, the Student Federation of the University of Ottawa (SFUO), to court to recover U-Pass funds after allegations arose that the SFUO did not properly administer the U-Pass referendum question.