Why is the Senate in recess at the moment. A source offers Malkin a tip:

“The move to put the Senate in recess was preemptive on Reid’s part. Putting the Senate in recess ensures that bill opponents cannot seek recognition on the Senate floor and thereby offer amendments or opposes the bill in any way. In sum, it is just one more tool Reid is using to silence dissent. So there you have it. The Senate is closed on a Tuesday afternoon on a day when we are dealing with the massive-in-scope immigration ‘reform’ bill.”

After all, we wouldn't want debate to get out of hand...