I've had this experience multiple times in this game : Teamkilling someone by mistake(because they get caught in a crossfire for example, or run towards where I just tossed a grenade, etc...)and because the team leader decided to pick on me he kicks me. On the other hand, I've seen team leaders getting frustrated with their own team and start team killing them on purpose, but because they're team leaders, nothing happens.
What kind of totally corrosive system is this? Instead of incentivising fair play it deliberately incentivises people to behave in a toxic fashion, which just establishes a terrible gameplay environment.
So here's a simple idea : Remove team leadership for starters, since it plays no role in the game anyway, apart from dividing the team into - those with rights and those without. And AUTOMATICALLY kick the player from the mission if he teamkills twice, or spends too much time afk.