An Orange County jury found a Shawkey, 47, guilty in June of murdering business partner Vendrick and dumping his body in the Pacific Ocean.
Shawkey was found guilty of special circumstances murder for financial gain. The jury also found Shawkey guilty of grand theft.
The prosecution said Shawkey took $1.2 million from Vendrick, 71, before killing him in 2008. Shawkey is accused of luring Vendrick onto a boat in Dana Point under the pretense of discussing a business deal. Prosecutors alleged Shawkey killed Vendrick and dumped his body in the ocean. Vendrick's body was never found.
Shawkey claimed he believed Vendrick was living somewhere in Mexico.
Vendrick was a retired man from Phoenix who had worked in the software industry. Prosecutors say Vendrick met Shawkey online several years ago. Shawkey corresponded with him via email until Vendrick trusted him with hundreds of thousands of dollars to put toward a software development plan.
Prosecutors say there was never any software development plan in the works.
