When DC Circuit Judge David Sentelle took senior status on Tuesday, that created a fourth vacancy on the nation's second most important court. Out of 11 judgeships, only seven are filled.

That has a serious impact on the caseload for the judges who are left. When the Senate confirmed Thomas Griffith to the eleventh seat in 2005, that resulted in there being about 121 pending cases per active judge.

According to the most recent data on pending cases made available by the Administrative Office of U.S. Courts, that number has been climbing in recent years, and with Judge Sentelle's departure, has now skyrocketed to about 188 cases per active judge.

This is not surprising. Several vacancies on the DC Circuit have opened on the court since President Obama took office, but Senate Republicans have prevented him from being able to get even one confirmed judge onto court.

In 2005, Republicans were eager to get President Bush's nominees onto the DC Circuit. With the caseload per active judge far higher than it was then, the need to fill vacancies is greater than ever.