Stories like this just emphasize the need for background and reference checks and certification for babysitters. I'm not talking about a degree here, I'm talking about a basic course in first aid and child care -- how to handle a crying baby, how to handle a biting toddler, etc. I believe that babysitters who take a course like this are not only more educated and skilled caregivers, but they also show a committment to what they do by taking the initiative to learn more.
If you engage in babysitting, I urge you to complete a course like those offered by the American Red Cross. In addition, keep handy a list of references for parents who may be utilizing your services. You can help "raise the bar" for babysitters and teach parents to expect more when it comes to choosing caregivers for their children.