3 plead guilty in Chinese spy case

The brother, sister-in-law and nephew of a Chinese American engineer who was convicted last month of conspiring to pass information about U.S. naval technology to China pleaded guilty Monday to charges stemming from the same case.

Tai Mak, 57, pleaded guilty in U.S. District Court in Santa Ana to violating export-control laws. His wife, Fuk Heung Li, 49, pleaded guilty to aiding and abetting the violation of those laws.

Their son, Billy Yui Mak, 26, pleaded guilty Friday to the same charge as his mother. All three live in Alhambra.

Chi Mak, 66, of Downey, was found guilty May 10 after a six-week trial of acting as an unregistered agent for China, lying to the FBI, conspiracy to violate export-control laws and attempting to violate export-control laws.

The trial of Chi Mak’s wife, Rebecca Laiwah Chiu, 63, is scheduled to begin today.

Chi Mak, a naturalized U.S. citizen, worked at Anaheim-based Power Paragon Inc., a firm with many Navy contracts. The FBI kept him under surveillance for 18 months using cameras, wiretaps and microphones hidden in his car and work cubicle.

He was accused of transferring unclassified data onto three encrypted disks, which prosecutors described as sensitive and embargoed from China. Mak’s brother and sister-in-law were arrested Oct. 28, 2005, just before boarding a plane to China with the disks.

The material included information on an electric propulsion system for warships, a solid-state power switch for ships and the future of power electronics.

During the trial, Chi Mak contended that the information, which he thought was in the public domain, was intended for friends in China interested in consumer electronics. Prosecutors said that one of the men was his contact with Chinese intelligence.

Prosecutors said Chi Mak was a sleeper agent who began preparing for his U.S. assignment in the 1960s, when he moved from China to Hong Kong, then a British colony. Federal agents said he admitted sending military-related documents to China, and they found thousands of pages of the files in his home.

Tai Mak and his wife are scheduled for sentencing Oct. 1. Their son is set for sentencing Sept. 24. Chi Mak, who prosecutors say could face up to 45 years in prison, is scheduled to be sentenced Sept. 10.

david.haldane@latimes.com