What crime is Victor accused of, and what piece of evidence is used to prove his innocence? Frankenstein by Mary Shelley

After the creature has left, Victor departs from his
cottage in order to take a walk where he determines to leave the village although he
feels that anywhere else he will be in danger.  As he strolls along the beach, some
fishermen pull up to shore in a small boat; they hand Victor a packet which contains
letters from Geneva, as well as one from Henry, encouraging him to join his friend in
Perth so they might turn southward together.  "This letter in a degree recalled me to
life," Victor remarks; he determines to leave the island in two
days.

But, before he departs, Victor must dispose of his
work.  As he looks upon the mangled flesh, Victor feels as though he has killed a
person, but he gathers his instruments and the flesh that lies promiscuously on the
floor and places it in a basket weighted down with rocks.  In a boat with the basket and
its hideous content, Victor take a boat out to dispose of his tools and the flesh. 
Then, he looks out to sea, which he believes will be his grave.  After a time, a sudden
swell creates large waves and Victor becomes ill.  Yet, he constructs another sail out
of some of his clothes, and he eagerly heads for the shore where there is a neat, little
town.  As he draws closer, Victor perceives that the villagers are huddled together in
an odd posture.  Instead of being cordial, one man answers Victor's question as to why
they have treated him with such wariness and coldness roughly.  Another man answers,  "I
do not know," said the man, "what the custom of the English may be, but it is the custom
of the Irish to hate villians. 

Victor is summarily
arrested and taken off to Mr. Kirwin, the magistrate.  Then, Victor learns that his boat
has been seen on the night of the muder of Henry Clerval.  In the presence of Henry, the
agonized Victor exclaims, " Have my murderous machinations deprived you also, my dearest
, also, Henry of life?"  Again, as when he has fashioned the female creatre, Henry feels
sick with the consderation of what he has caused.  At times he asks his attendants for
help in destroying the creature who torments him.  He passes out, and when he comes
to, Victor finds himself locked up in prison for the murder of Henry Clerval. However,
when the time of the trial comes, Victor is acquitted as there is evidence that he was
on the Orkey Islands at the time of the murder.