Research Brainstorm

I am studying teacher tenure because I want to find out how it affects teacher performance in order to determine whether tenure should be eliminated or reformed. My audience is those with power in education. I'm writing to the people of an opposing view because there is no point in persuading someone that already agrees with you. I reckon that they disagree with me because they feel that tenure is the only means of job security available to teachers and that without it, the teacher shortage will become even greater. They worry that taking away tenure would make less people want to go into teaching, which is a valid point. But I wonder if there are better ways to increase interest in the teaching profession. I venture to argue that teacher tenure removes teacher's motivation to continue or improve effective teaching.