Mark,
All the quotes I've seen give the chair voltage as between about 1700 and 2600V, although in many cases they apparently reduce the voltage after a few seconds. A quick search came up with these:

GA: 2000V 4 sec, 1000V 7 sec, 208V 2 min.
AL: 2500V 20 sec, 250V 100 sec.
VA: 1825V 30 sec, 240V 60 sec.
??: 2400V 7 sec, 600V 17 sec.

The initial higher voltage is supposed to knock out the brain & nervous system instantly.

George,
Trying to place where that would have been from the list I have here in conjunction with your location. You said state, but would that by any chance have been the District of Columbia? Just morbid curiosity!

I seen an oft-quoted value of just 32 volts as being the lowest potential which is on record as having proved fatal.