These are tough times for teachers. It doesn't matter whether you teach in a public or private school setting. You expose yourself to legal risks every single day on the job.
So, let's look at liability from our point of view as teachers. (I am not an attorney, so read my general layperson's comments and observations then run questions by and seek advice from your attorney.) This mnemonic DIRE lays out some of the issues we need to watch for. Protecting yourself is so important. Nobody else will look out for your interests as well as you will.
Your chances of getting sued are probably on a par with having an accident while driving. When you drive carefully, observe the rules of the road, stay alert and drive defensively, most of the time you will be OK. But, things happen for which you are not to blame. Like the time I came down one morning to get into my car to drive to work. Somebody had backed into the front end of my vehicle. Thank goodness I had insurance. Double thanks that the person who backed into my car left a note with her contact info and an apology together with a statement that her father would pay for the repairs.
In the old days most of us professionals would keep a day book. You kept track of your appointments and schedule in it. We also used it to document what was said and discussed at interviews and meetings. Our recollection of events diminishes rapidly within days of a meeting. The hours and what was said all run together after a while. That's why it is so important to have a record of events which have occurred and what was discussed.
Fast forward to 2013. Google and other free, widely available email providers allow all us to keep track of everything electronically. So convenient and available anywhere any time via handhelds. The only caveat I have here is that you need to make certain that you keep records and notes in your personal email, not the school's. You control your personal email, calendars, documents, etc. You do NOT control the school's email. Period.
What should you document? Meetings with students, incidents which occur both in and out of the classroom and staff lounge, conversations with parents, meetings with parents, meetings with administrators. When somebody decides to sue you or you find yourself being asked to testify about some incident, your careful electronic notes will add to your credibility.