They are always pressured to do so at the risk of losing their careers.
Anyway, more info about the cheating scandal in D.C.:
What may be the most most egregious case is at Langdon Education Center, where there are also allegations of cheating in years prior to 2012, the year that is the focus of the new report. Concerns about widespread cheating over the years on high-stakes tests in D.C. schools were heightened late last week with the publication of a 2009 memo that raised suspicions about nearly 200 educators cheating on the 2008 test, when Michelle Rhee was schools chancellor.
The report mentioned in the article