Christopher Matthews, a Canadian, will serve as the party's deputy political director under an immigrant work visa when his tenure begins on Oct. 1, according to the group's spokesman.
But the Federal Election Campaign Act prohibits foreign nationals from having any involvement, direct or indirect, with campaign finances and decision-making powers in a political committee.
Matthews is a foreigner under the law, said Kenneth A. Gross, a Washington, D.C., election law expert and partner at the Skadden, Arps, Slate, Meagher & Flom firm. Gross also served as former associate general counsel of the Federal Election Commission.
Matthews "sounds like he's got a problem," Gross told ABC News.
Hector Barajas, communications director for the state party, said Matthews' responsibilities as deputy political director will include political research, involving microtargeting potential voters and technology. Matthews will only be involved in contributions and expenditures that relate to the political department, Barajas said. And "he won't necessarily be the one writing the check" to pay for purchases, Barajas added.
From May until his October start date as deputy political director, Matthews will be working for the California GOP as a management consultant, and networking with the state, county and volunteer parties, according to the spokesman.
The law is "very broad," said Larry Norton, a D.C.-based lawyer at the Womble Carlyle Sandridge & Rice firm who served as general counsel of the FEC from 2001 to 2007.
"[He] seems to be in a key position running a major state party committee, and he's a foreigner," Norton told ABC News. "Under the letter of the law, it looks problematic."
The San Diego GOP party originally hired Matthews in 2004 as a consultant, according to Barajas. Matthews has been with the state GOP for about a month, Barajas said.
Matthews currently works under a NAFTA visa that permits nonimmigrant Canadian and Mexican citizens to work in the U.S., Barajas noted.
When asked about the legal implications of Matthews' employment, Barajas referred questions to Charles Bell, the Sacramento-based attorney he said has been handling this matter for the party. Bell reiterated Barajas' statements regarding Matthews' duties. "We are satisfied that we have fenced him off from anything that has presented a problem there," the lawyer told ABCNews.com
This post has been updated.