http://www.m-w.com/cgi-bin/mwwodarch.pl?Jul.26
Did you know? "Judgment" can also be spelled "judgement," and usage experts have long disagreed over which spelling is the preferred one.Henry Fowler asserted, "The OED [Oxford English Dictionary] prefers the older and more reasonable spelling. 'Judgement' is therefore here recommended."
William Safire held an opposite opinion, writing, "My judgment is that Fowler is not to be followed." "Judgement" is in fact the older spelling, but it dropped from favor and for centuries "judgment" was the only spelling to appear in dictionaries.
That changed when the OED (Fowler's source) was published showing "judgement" as an equal variant.
Today, both spellings of the word are common. "Judgment" appears to be more popular in the U.S., whereas "judgement" is slightly more frequent in Britain.
I am aware of the "controversy" - I do not consider them equal variants however - as an attorney (at least here in California), I have never seen the "judgement" spelling used in legal work. I think it would be safer for Zac's Mom to use "judgment" for an American audience : )