an of operation.

If it was agreed that the prisoner should be there to assist, it is
enough. If they thought the place proper for their purpose, according to
their plan, it is sufficient. Suppose we could prove expressly that they
agreed that Frank should be there, and he was there, and you should
think it not a well-chosen place for aiding and abetting, must he be
acquitted? No! It is not what _I_ think or _you_ think of the
appropriateness of the place; it is what _they_ thought _at the time_.
If the prisoner was in Brown Street by appointment and agreement with
the perpetrator, for the purpose of giving assistance if assistance
should be needed, it may safely be presumed that the place was suited to
such assistance as it was supposed by the parties might chance to become
requisite.

If in Brown Street, was he there by appointment? was he there to aid, if
aid were necessary? was he there for, or against, the murderer? to
concur, or to oppose? to favor, or to thwart? Did the perpetrator know
he was there, there waiting? If so, then it follows that he was there by
appointment. He was at the post half an hour; he was waiting for
somebody. This proves appointment, arrangement, previous agreement; then
it follows that he was there to aid, to encourage, to embolden the
perpetrator; and that is enough. If he were in such a situation as to
afford aid, or that he was relied upon for aid, then he was aiding and
abetting. It is enough that the conspirator desired to have him there.
Besides, it may be well said, that he could afford just as much aid
there as if he had been in Essex Street, as if he had been standing even
at the gate, or at the window. It was not an act of power against power
that was to be done; it was a secret act, to be done by stealth. The aid
was to be placed in a position secure from observation. It was important
to the security of both that he should be in a lonely place. Now it is
obvious that there are many purposes for which he might be in Brown
Street.

1. Richard Crowninshield might have been secreted in the garden, and
waiting for a signal;

2. Or he might be in Brown Street to advise him as to the time of making
his entry into the house;

3. Or to favor his escape;

4. Or to see if the street was clear when he came out;

5. Or to conceal the weapon or the clothes;

6. To be ready for any unforeseen contingency.

Richard Crowninshield lived in Danvers. He would retire by the most
secret w