We are nothing if not current.
An article published in 2003 about effective subheadings, available here for the clicking, was referenced at the top of a “legal writing” Google search I just did. Authors Kara Thompson and Zach Brez for the Writing Center at the Georgetown University Law Center, did a fine job in this short piece explaining the importance of the “point heading.” (Except please don’t make subheads all caps; typical sentence style, boldfaced, is better.)
Don’t be lazy about drafting the subheadings. Sometimes they will be the most important part of your brief.
Conventional wisdom says to limit your subheadings to one sentence. But that’s not necessarily best practice.
Have you ever encountered a cold court? Sometimes judges don’t have the time or the desire to read your brief thoroughly, or at all, before your case is called. I’ve watched judges leaf through my motion or my brief during oral argument. I want that judge to understand my positions. One-sentence subheadings don’t always accomplish that.
So by all means, make those subheads incisive and argumentative, and a little bold. And don’t be afraid to give the judge more help understanding your positions with a longer subheading.