Sanhedrin 35: Can the Death Penalty be Delayed? When is Shabbat Overriden?

Today's daf focuses on death.  Well, not death, exactly, but on the death penalty.  The rabbis want to understand more about what to do with a verdict that requires capital punishment.  The Gemara notes that monetary sins are begun and finished their trials during the day.  Only one capital case can be heard on the same day.

Some rabbis believe that judges should delay their verdicts and others believe that verdicts should be handed out on the day of the trail.  Is is permitted to hear a case on ere Shabbat?  There are concerns about rabbis changing their minds, and other wives feeling 'weak' with a wait to complete the verdict.

Does a met mitzvah, a mitzvah done for the sake of improving a person's dying days, justify breaking Shabbat?  For example, wouldn't a nazarite circumsizing his son stop and return home if his sister has a baby?  Doesn't he risk becoming ritually impure?  What overrides Shabbat and what overrides the requirement to work?  The rabbis debate these points.