Considering that the source is WND, I suspect we are getting only one side of the story.
http://www.boston.com/news/local/articles/2005/04/29/arrested_father_had_point_to_make/
Parker said he met with school officials to gain those assurances and then refused to leave until he got them. Parker stayed at Estabrook School for more than two hours, according to Superintendent William J. Hurley, as officials and Lexington police urged him to leave. Finally, they arrested him for trespassing.
Parker, who refused to bail himself out of jail Wednesday night, said he spent the night in custody to prove a point.
Sounds like he chose to engage in a little civil disobedience in order to make a point.