I really wish we had more than tweets to go by. I have a hard time believing that the judge is dismissing potential jurors just because they have prejudged JA's guilt. The jurors, when they are selected, will be instructed that JA's guilt is no longer at issue. I assumed that they were only tossing people who had prejudged death vs. life, but from the tweets it sounds like people are being dismissed just for believing something they will be instructed to accept as true anyway.
They should be asking whether anyone believes there is doubt as to her guilt or cruelty of the murder, or if anyone believes the first jury made a mistake, and then asking if those people are able to set aside those feelings and accept the instructions of the court.
Hopefully JM will ask those questions down the road, but in the meantime he's losing potential jurors if these tweets are accurate!