Warm emitters have a lower blue peak and overall less blue light, so I'd say they can hardly be classified as sleep murderers. For example, the SST-20 3000K:
Source: Test of a Luminus SST-20-W 3000K 95CRI led
That blue peak still looks a bit high compared to other high CRI emitters, check the thread: SKV89's LED Strips and bulbs test results 