What Happens to a Teacher with "U" Ratings?

By way of explanation, a "U" refers to "unsatisfactory" performance in the New York City public schools, but there are similar ratings in all school districts in the country.

However, as readers of this blog know, or should know, the "U" is being misused widely by principals who simply want to get rid of undesirable teachers, and they are being told to do it by the higher-ups in NYC schools, i.e., Bloomberg and Klein. This is being done to save money on pensions.

From the NY teachers' chatboard of Teachers.net:

I really need some information. A teacher I know - he has
been teaching 20+yrs, has recieved 3 U's in the past few
years. He was apparently removed from our school today.
How long does the school have to keep them on the payroll?
They can't hire a sub or an ATR until the teacher is off
the payroll and I have been pulled from my small group
reading to teach this class.

This post got a couple of to-the-point answers:

You sound like the only reason you want a response on this is
because you are being inconvenienced by the teacher's
predicament. In that case, screw you. A proven, S-rated
teacher starts getting U ratings in the twilight of his/her
career and you don't question that, only when can they fill
the position so you don't have to work so hard?
Someday you too may be the victim of Kleinbloom's age
discrimination and I hope you get just as little sympathy.
Scores of wonderful older teachers are suddenly finding
themselves the recipients of U ratings as a way to force them
out -- teachers who were mentors, who served on curriculum
committees, who were rated S for 15, 20 years. Suddenly
their experience and salaries are a detriment to the
administration and they are being targeted. But you just
want to get back to your old schedule. I bet you are a
Teaching Fellow.

And this:

You can betcha that the goal is to take away the pension that she
spent her whole life working for, on some trumped up charges.
That is what happens, and you have to hire a lawyer to try to
prove you are innocent.

"To prove you are innocent."--This is what happens in "due process" hearings--you have to prove yourself "innocent" of whatever bogus charge is brought. The hearing officers decide on the basis of "the preponderance" of "evidence"--evidence that is typically doctored or in the case of witnesses perjured--whether you get reinstated to your job--a near impossibility--or whether the principal's dismissal is upheld, which is almost always the case.