With the 60-day limit established in the War Powers Act expiring today, the Obama administration has yet to acquire authorization from Congress for ongoing military operations in Libya. Robert Chesney outlines two possible legal arguments they could make in response--either they "to halt all US operations altogether for a temporary period, and then asserting that the clock should start from scratch when operations later resume," or they could stop everything they're doing with regard to Libya.
The latter option–i.e., suspend-all-operations-period–is bad from both a legal and a policy perspective, if you ask me. It's bad legally insofar as the operational pause is a conceded fiction (“The administration apparently has no intention of pulling out of the Libya campaign,” Charlie writes…), in contrast to a situation in which our participation in hostilities stops and it truly is not clear whether we will resume that participation. And it is bad from a policy perspective because, I am assuming, an actual suspension of US-provided ISR, e-warfare, logistical support, and so forth, would greatly hobble the NATO effort at a time in which the rebels are just beginning to find their footing with the aid of enhanced close-air support (I could be wrong about those consequences, but if I'm correct then it seems to me that this option comes with a pretty high price tag in terms of lost momentum, or worse).
The former option is the better of the two (see here for my earlier take on this rationale), assuming that this is not also a complete fiction. That is, I think the argument is a defensible one if in fact we are reverting to a mere-support role, with no specific expectation of resuming drone strikes after a brief respite meant merely to turn off the clock. That said, it's not an obviously correct argument. There is still plenty of room for debate as to what degree of involvement in hostilities implicates the WPR's notice requirement and what degree of retrenchment suffices to stop the clock.
But both options seem like gaming the system. It's never been clear to me why the administration didn't just ask Congress to pass a resolution approving the operation, and the only reason I could can come up with is that the administration didn't want to create another "hostage" situation by asking House Republicans to do so. The result either way, I think, is exactly what Bruce Ackerman and Oona Hathaway argue--"future presidents will simply cite Libya when they unilaterally commit America to far more ambitious NATO campaigns."