[elwoodblues]

For those interested, part of the reason for the huge difference in costs is that virtually 0% of death penalty cases are ever plea bargained whereas the VAST majority of non-capital cases are. Trials are expensive and capital cases last longer. Case in point -- Susan Smith offered to plead guilty and accept life in prison with no possibility of parole. State rejected the offer wishing to seek the death penalty. A lengthy and costly trial was held. She was found guilty and sentenced to, you guessed it, life in prison without the possibility of parole. The state risked
getting a not-guilty verdict (or a lesser sentence) at a huge cost for the benefit of the possibility of a death sentence vs. a 100% guarantee of life in prison with no parole. They accepted a stupid gamble and cost the taxpayers a lot of money in the process. That's just not a good bet.
Expert witnesses are expensive. Essentially, the state tries to dot it's i's and cross it's t's knowing that there is a mandatory appeal process.