Most judges are happy to see a shorter, more succinct cover letter. Their time is valuable, and they do not have the resources to put into the hiring process that larger organizations do. While it is important to let the judge know your reason for pursuing the position, there is no need to go into great detail. Do make sure that your cover letter contains no mistakes of any kind, though; many judges look at the cover letter as a mini-writing sample and will not consider an intern with typographical or factual mistakes in his or her letter.
If you are applying to an area of the country to which you have a particular connection, this is a good chance to highlight it, particularly if it is not reflected elsewhere in your materials. However, if your connection to the area is tenuous, it is best not to mention it at all. If the reason why you are applying to a court is not obvious, you should make sure to explain your reasons for applying as well.
On the following pages are three sample cover letters. The first is a generic letter containing only the basics. The second is a more substantive cover letter for individuals who prefer to include more information about themselves in their letters. The third is a letter highlighting some points you might like to share with a judge. Any of these formats are fine, but please do not copy the samples word for word — your letter should reflect you as an individual (and a judge will realize that you have merely copied the sample when he receives 15 identical letters!)
Sample Letter 1 (A generic cover letter)
Sample Letter 2 (A more substansive cover letter)
Sample Letter 3 (A letter explaining ties)