By Mary Slosson

LOS ANGELES (Reuters) - Trust Company of the West plotted to fire its star bond fund manager Jeffrey Gundlach before he and his inner circle ever began downloading information, Gundlach's lawyer told jurors.

TCW then covered up its plans in a "conspiracy of silence," attorney Brad Brian said on Tuesday.

"They shot him without warning. This was not a random act. It was premeditated," Brian said, referring to TCW's sudden termination of Gundlach.

Brian's presentation in a Los Angeles courtroom marked the final day of arguments in the high-stakes trial with hundreds of millions of dollars at stake.

TCW, a unit of French bank Societe Generale <SOGN.PA>, fired Gundlach in December 2009 and sued him a month later, accusing him of stealing trade secrets, plotting to form a new company using TCW proprietary information, and gutting the firm of its entire mortgage-backed securities team.

Gundlach fired back with a counter-lawsuit, alleging that his former employer owed him hundreds of millions of dollars in compensation and had secretly plotted to fire him while he was still chief investment officer.

In the weeks following his termination, Gundlach went on to form DoubleLine Capital, along with three of his co-defendants in the case. Roughly 45 TCW employees, largely from the mortgage-backed securities group, followed.

The warm courtroom was packed on Tuesday, with audience members sitting shoulder to shoulder. Gundlach sat in the front row, at the center of the bench.

TCW attorney John Quinn said in his closing statement that Gundlach and his inner circle plotted to destroy TCW by forming their own company at TCW's expense.

"They essentially stopped working for TCW, and worked against TCW," Quinn told jurors. "And they did all these things while drawing their very generous paychecks."

Jury deliberations are expected to begin on Wednesday morning.

The case in Superior Court of California, County of Los Angeles is Trust Co of the West v. Jeffrey Gundlach et al, BC429385.

(Reporting by Mary Slosson, editing by Dan Levine, Ted Kerr and Matthew Lewis)