Teacher tenure?

Ever since I read this Washington Post story about a teacher being dismissed I've been haunted by it. You read it and hope it is one sided- that the school district isn't revealing important details that back up their case. You hope  that none of it can be true. And I don't know- there is probably a lot more to the story.

But I do know that I've worked for a principal who would do exactly what was written about here (Not a principal at the think tank, where I work now). I know that this can happen. In the cases I know of it happening the teachers decided to look for another school before it got this bad- and most found a much better fit at another school where they went on to shine.

 But this situation is not out of left field. 

I hate for this to be supported as a case for using test scores as a significant portion of teacher evaluations because I do not think that is the answer. But what is the solution? Better structured observations from principals with a check list of what they observed?  Something like DCPS has in place where outside observers observe teachers? My husband's company does 360 Reviews where a sampling of everyone he works with gives feedback. Would something like that help give a bigger picture of what is occurring inside classrooms?