"[5] Among his more notable cases were the sentencing of former Texas Attorney General Dan Morales (for mail fraud and filing false tax returns)[citation needed] and the trial of Gary Paul Karr for federal wire fraud (in connection with the kidnapping and murders of atheist Madalyn Murray O'Hair and her son and granddaughter).

This case found its way into court following a dispute over payment of fundraising expenses by the failed Republican Senate campaign of Dick Thornburgh.

In 1998 Sparks issued stays of execution for Joseph Stanley Faulder and Danny Lee Barber, holding that the Texas Board of Pardons and Paroles failed to provide due process in considering their requests for clemency.

[citation needed] In 2010, he became the second honoree in the history of the American College of Trial Lawyers' Sandra Day O'Connor Award.

"[7] In 2006 he handled a case involving the Texas Republican Party's effort to get former Congressman Tom DeLay's name removed from the ballot in the 2006 Congressional Election.

DeLay won the Republican primary election in March, but resigned from Congress in early April during a corruption scandal.

And although officials at Hutto might be making changes now, he noted, didn’t Lawrence have a feeling it was merely because the defendants knew, on account of the lawsuit, that 'the hammer was coming down?"

[13] In 2012 the court commemorated his 20 years served on the federal bench and marked the occasion with a portrait painted by artist Michele Rushworth.