The judge told Barry he had to appear before sentencing, when Barry wanted to leave during closing arguments. As no verdict had been determined, a defense attorney would have immediately asked for a mistrial. The judge anticipated a guilty verdict, in front of the jury.
When The Flash begins to subdue Fallout, the meta overtakes 10,000 rads of emanating radiation. Assuming that the emission of radiation is that of gamma rays (the stereotypical green aura), this output would equal roughly 100,000 mSv of radiation. A dosage of this magnitude would be fatal, even as an instant exposure. Barry was exposed to this radiation for a long period of time, meaning that he would have literally no chance of surviving this exposure.
The writers clearly don't understand radiation or basic science. It's the ozone layer which protects Earth from radiation, not the vacuum of space.
When announcing the trial verdict, the voice of the jury foreman lists the case as docket 5677-B but his lips say 5567-B (as does the Closed Captions, for that matter).
Cecile does not present a defense for Barry because he refuses to testify. However, Barry's testimony is not the only part of the defense she could have presented. She could have asked Iris to testify that the murder weapon was not included in the wedding gift that they opened together. She could have also asked Joe and the other guests at his Christmas party to testify that Barry was at the party so he would not have had time to commit the murder.