"Punctuation police"

What's worse than a "grammar Nazi?"  Perhaps a "punctuation policeman."

Teachers have attacked the "punctuation police" who have marked down children's SATs for incorrectly drawn commas and semi-colons. Frustrated staff complained about the new mark scheme on social media after children were penalised for drawing punctuation points at the wrong level or failing to draw apostrophes with sufficient curve. Teachers said that their pupils had been marked down for semi-colons which were too high on the line...

Some comments at the Telegraph article suggest that the problem lies with the teachers failing to instruct the students in the proper manner of denoting punctuation marks.