She was not without scandal. Inappropriate emails between /*Chuck Rosenthal*/ and Siegler's husband surfaced earlier this year. She also was criticized for excluding Lakewood Church members from juries.
"There's nobody in the country who is more prepared than Kelly is," said Assistant District Attorney Paul Doyle. "When she gets focused and motivated on a case, she puts it together. She anticipates everything that's going to happen. She anticipates every defense attorney's move. You cannot surprise her."
Siegler is already signed up to help prosecute the Wharton County capital murder case of James Freeman in August. He is accused of killing Texas game warden Justin Hurst.
Siegler, who did not return calls Friday, has not announced any further plans.
Kenneth Magidson is currently serving as Harris County DA until December. Former judge Pat Lykos and former Houston police Chief CO Bradford will face each other in the general election.