I'm working on a murder mystery, in which the victim is electrocuted
with a radio dropped into the bath, but it is unclear (at first)
whether the death may have been an accident.  My question has to do
with what would have been observed when the victim is found.  The
murder takes place in an old (c. 1880's) mansion.  Specifically, I'm
wondering:  (1) Would the electricity have gone out as a result of the
electrocution, such that the lights would not be working when the
victim is first discovered;  (2) Would there be any danger of
electrocution to the person who first has contact with the body;  (3)
Presuming the victim died from the fribillation of the heart (and not
from drowning), and presuming that he was not found until nine hours
after the electrocution took place, what would the scene look like; 
and (4) Given the fact that the victim has a heart condition, would an
autopsy following such an electrocution be able to rule out the
possibility that the victim had a heart attack and accidentally pulled
the applicance into the bath?

---

Clarification of Question by mysterywriter331-ga on 07 Jul 2006 07:39 PDT

By way of clarification, the mansion dates to the 1880's, but the
murder takes place in the present.

Hi mysterywriter331-ga,

Taking your questions one by one:

WOULD THE ELECTRICITY HAVE GONE OUT?

It's possible but unlikely. According to a number of sources,
including this Lab Safety document...

   Safety in the Laboratory
   http://www.colorado.edu/physics/phys3330/phys3330_fa05/pdfdocs/LabSafety.pdf

...fibrillation sets in at around 100 milliamps of flow through the
body. Above around 200 milliamps, the heart is clamped so tightly that
fibrillation does not occur - but the victim will still die if not
found immediately, because breathing is impossible.

There would also be current flowing through the bathwater - an
informal discussion on this page estimates it to be around 120
milliamps:

   Electrical Shock
   http://www.codecheck.com/ecution.htm

Suppose the total current flow (body plus water) is 250 milliamps.
That's a quarter of an amp. A household fuse in a very old building
might be as little as 5 amps, but even so the electrocution current
alone isn't going to blow the fuse.

If, however, other appliances are operating that are near the fuse
limit, the electrocution current could take the total current above
the level that blows the fuse. That's probably what happened in the
situation described by pinkfreud-ga in the comments.

In a newer property, protection might be provided by a ground fault
circuit interruptor (or residual current device) in addition to a fuse
or circuit breaker, in which case the circuit should certainly go dead
in less than a tenth of a second (but in that case the victim would
probably survive).

Also bear in mind that most houses have more than one electrical
circuit. If the fuse blows on the circuit that powers the radio that
was dropped into the bath, it isn't necessarily going to blow the fuse
that powers the lights.

DANGER TO THE FIRST PERSON WHO HAS CONTACT WITH THE BODY

If the fuse has blown, the power is off and there is no risk to the
person who contacts the body (assuming the fuse is on the "live" side
of the circuit, and that the "return" or "neutral" side is close to
ground potential).

If the power is still on, and someone touches the body or puts their
hand into the water, they will get a shock. Provided there is no path
through their heart the risk will not be so high as for the person in
the bath. For example, if they are standing on dry flooring and put
just one hand into the water they are likely to survive, but if they
are leaning against a grounded metal object when they reach a hand in
they could die.

THE SCENE NINE HOURS LATER

If the bath plug does not make a good seal, the bath will have drained
dry. Otherwise, the victim's skin is going to look really wrinkled
from the prolonged contact with the water ("prunation"). Prunation
does not go away after death, even if the water is removed.

Rigor mortis (where the muscles become hard due to increased ATP and
lactic acidosis) will be near its peak.

Livor mortis will also be near its peak.

  "During livor mortis, the body becomes distended and
   skin colour progressively changes from green to purple
   and finally to black. The dependent areas of the body
   undergo this process first due to the pooling of blood,
   and this is usually seen within 2 hours of death, with
   the process of livor mortis reaching its maximum at
   8-12 hours."

   Wikipedia - Death
   http://en.wikipedia.org/wiki/Death

WOULD THE AUTOPSY BE ABLE TO RULE OUT A HEART ATTACK?

Certainly, yes. A "heart attack", or myocardial infarction, causes
scarring of the heart tissue which would be easily detected by the
Coroner.

Maybe you are using the term "heart attack" loosely, to include
cardiac arrest, in which case the question becomes more interesting:

  "Ventricular fibrillation (VF) constitutes the most
   common electrical mechanism in cardiac arrest, and
   is responsible for 65 to 80% of occurences..."

   Wikipedia - Cardiac Arrest
   http://en.wikipedia.org/wiki/Cardiac_arrest

I'm not aware of a way the Coroner could easily distinguish between
fibrillation caused by an electric current, versus fibrillation
followed almost immediately by an electric current.

A research article mentions that, of six cases of death in a bathtub
with a hairdryer, none showed electrical burns (because the
electricity flow is distributed across a large part of the skin when
the victim is in a bath). Some victims showed petechial haemorrhages
which are assumed to be due to the combination of cardiac arrest and
muscle contractions:

   Electrocution--autopsy study ... "electrical petechiae"
   http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12062943&dopt=Abstract

If cardiac arrest and muscle contractions the cause, the petechiae
might also be present at autopsy if the fibrillation occurred just
before the electrocution.

The forensic examination of the bathroom is likely to reveal some
clues. Perhaps there are some tiny chips where the radio banged
against a shelf or the edge of the bath on its way down, or other
clues as to how the appliance came to be in the bath.

Let me also refer to you a very extensive question and answer posted
to Google Answers in 2003:

  "I'm working on a murder mystery, and I need to know
   how the effects on the human body of electrocution
   when an appliance is dropped in bath water are different
   from the effects of electrocution when a person
   comes into contact with power lines.  During an autopsy,
   could a medical examiner tell the difference and how?"

   Forensic medicine electrocution
   http://answers.google.com/answers/main?cmd=threadview&id=172938

In his answer, tutuzdad-ga provided enough material about autopsies
that you could weave your story whichever way you wanted.

Good luck with your murder mystery!

Regards,
eiffel-ga


Google Search Strategy:

electrocution "how much current" heart
://www.google.com/search?q=electrocution+%22how+much+current%22+heart

autopsy electrocution
://www.google.com/search?q=autopsy+electrocution

"electrical petechiae"
://www.google.com/search?q=%22electrical+petechiae%22


Additional Links:

Wikipedia - Electric Shock
http://en.wikipedia.org/wiki/Electric_shock

Wikipedia - Ventricular fibrillation
http://en.wikipedia.org/wiki/Ventricular_fibrillation

Wikipedia - Myocardial infarction
http://en.wikipedia.org/wiki/Myocardial_infarction

The answer was quick and thorough, responding to each aspect of my
question with more-than-sufficient detail.  I'm grateful for the
effort to go beyond what I asked, pointing me toward some trace
evidence that I might not have considered.  Thanks also for the links
to help with my own additional research.  I would be delighted to work
with this researcher again.

Such a thing certainly might blow a fuse and cause the lights to go
out (on that circuit). I used to live in a WWI-era house that had been
turned into several apartments. Once a neighbor in the adjacent
apartment accidentally knocked a blender into a sink full of water.
Not only did my neighbor's electricity cease, but so did mine. Turned
out that the entire south side of the house was on one electrical
circuit. Until the landlady replaced the fuse, we were in the dark.

Thanks, mysterywriter331-ga, for your kind comments and tip.