Lawyer's 'Colorful Insults' Crossed a Line, 6th Circuit Panel Says ("We cannot dismiss the disparaging statements in this case as mere stylistic flourishes or vigorous advocacy," Judge Amul Thapar of the U.S. Court of Appeals for the Sixth Circuit wrote.) and "There are good reasons no to disparage your opponents, especially in Court filings"
The ABA Journal has an interesting article here about a law prof who polices the language in SCOTUS opinions.
For pro pers, the LA Law Library offers Appeals: How the Court Process Works