CORPUS CHRISTI - A civil trial involving a Corpus Christi police officer accused of using excessive force in the death of a Sinton man began in federal court today Here's a look at the facts in the case:

28-year old Sylvester Villasana was shot and killed Mmay 9th, 2009 -- near Port and Ayers -- after leading police on a chase.

Officers say Villasana was holding a knife when he got out his vehicle. They tried to subdue him with a taser, and when he kept resisting, officer Justin Sanders shot him.

A Nueces County grand jury reviewed the details of the shooting and decided not to press charges against officer sanders. However, the Villasana family disagreed with the grand jury's decision and they are now suing both sanders, and the city.

The prosecution claims Sylvester Villasana did not have knife when he got out of his car, after leading police on a chase. However, the defense said Villasana not only had a knife, but also had "suicide by cops syndrome," saying the man had told others, in the weeks before the shooting that if police ever came after him he would want officers to take him down.

In court, witness Javier Hernandez said he saw officer Sanders taze Villasana.

"He put his taser down, pulled out a revolver and started shouting orders," Villasana said. He said he saw a phone in one of Villasana's hands and said the other one was empty.

He said, he saw sanders shoot Villasana three times, and that Villasana never lunged forward.

But the defense played Hernandez's videotaped statement to police, in which he said Villasana lurched forward -- towards the officer.

Hernandez said, after the shots were fired, police told him to get out of there, but sanders came after him saying, "Stop! You're my witness."

When prosecutors asked the witness to describe officer Sanders, Hernandez called him a "short, stocky, Caucasian"
This prompted the defense to point out a large problem with the way Hernandez's ability to remember important details.

Officer Sanders is not short, stocky and Caucasian. He's African-American.

Here's a look at what's next in the trial:

Tomorrow, the prosecution will continue calling witnesses who say, Villasana did not have knife.

The defense will be playing a recorded police transmission from the evening of the shooting.

Officer Justin Sanders is also scheduled to testify.