The 2 presumptions that apply to every criminal trial are the presumption of innocence and the presumption of sanity. I'd like to see a brief definition of them.

I'd like to see an explain on what the prosecutor needs to do to rebut the presumption of innocence and why the prosecutor needs to do this (standard of proof).

Finally, I'd like to see an explanation on what the defendant needs to do to rebut the presumption of sanity and why does the defendant needs to do this (standard of proof).

Can pretrial publicity affect the presumptions and unfairly influence a criminal trial? If yes, what can court do to minimize or eliminate such effects on criminal trials?