France doesn't have jury trials (ie where guilt or innocence is decided solely by members of the public) in the way the UK does. The theory is that judges, being superior by birth, will be immune to prejudice and fallacious reasoning, and able to control civilians by lecturing them.
In the UK, guilt or innocence is decided by Muggles alone, so it is necessary to shelter them from information that might lead them astray. Hence, it might lead to a trial collapsing if some wanker with a phone starts broadcasting information on the internet that the jury is not supposed to know about.
I am a French avocat, I know.
France does have jury trials in serious criminal cases and I have to say that I prefere Magistrates.