Official Rules of Racquetball
4.4 - Out Serve in Doubles
(a) Out-of-Order Serve. In doubles, when either partner serves out of order, the points scored by that server will be subtracted and an out serve will be called: if the second server serves out of order, the out serve will be applied to the first server and the second server will resume serving. If the player designated as the first server serves out of order, a sideout will be called. The referee should call "no serve" as soon as an out-of-order serve occurs. If no points are scored while the team is out of order, only the out penalty will have to assessed. However, if points are scored before the out of order condition is noticed and the referee cannot recall the number, the referee may enlist the aid of the line judges (but not the crowd) to recall the number of points to be deducted.
(b) Ball Hits Partner. A served ball that hits the doubles partner while outside the doubles box results in loss of serve.