Wesley Corman - the dentist. Had he successfully framed his wife she would have been committed to an institution and when questioned he justifies it by saying something like 'it was no worse than what you both had planned for me'.
Wes Corman was - in my opinion - the lowest of lows in the series. 100% no remorse both for the killing and framing his sickly wife. Hope he got the chair; throw the switch!