it follows that the jury were to judge of
everything involved in the trial; that is, they were to judge of the
nature of the offence, of the admissibility and weight of testimony, and
of everything else whatsoever that was of the essence of the trial. If
anything whatever could be dictated to them, either of law or evidence,
the sentence would not be theirs, but would be dictated to them by the
power that dictated to them the law or evidence. The trial and sentence,
then, were wholly in the hands of the jury.

We also have sufficient evidence of the nature of the oath administered
to jurors in criminal cases. It was simply, that _they would neither
convict the innocent, nor acquit the guilty_. This was the oath in the
Saxon times, and probably continued to be until Magna Carta.

We also know that, in case of _conviction_, the sentence of the jury was
not necessarily final; that the accused had the right of appeal to the
king and his judges, and to demand either a new trial, or an acquittal,
if the trial or conviction had been against law.

So much, therefore, of the _legem terrae_ of Magna Carta, we know with
reasonable certainty.

We also know that Magna Carta provides that "No bailiff (_balivus_)
shall hereafter put any man to his law, (put him on trial,) on his
single testimony, without credible witnesses brought to support it."
Coke thinks "that under this word _balivus_, in this act, is
comprehended every justice, minister of the king, steward of the king,
steward and bailiff." (2 Inst. 44.) And in support of this idea he
quotes from a very ancient law book, called the Mirror of Justices,
written in the time of Edward I., within a century after Magna Carta.
But whether this were really a common law principle, or whether the
provision grew out of that jealousy of the government which, at the time
of Magna Carta, had reached its height, cannot perhaps now be
determined.

We also know that, by Magna Carta, amercements, or fines, could not be
imposed to the ruin of the criminal; that, in the case of a freeman, his
_contenement_, or means of subsisting in the condition of a freeman,
must be saved to him; that, in the case of a merchant, his merchandise
must be spared; and in the case of a villein, his _waynage_, or
plough-tackle and carts. This also is likely to have been a principle of
the common law, inasmuch as, in that rude age, when the means of getting
employment as laborers were not what they are now, the m