CAMP LEJEUNE — The court martial begins for a Marine pilot charged with 20 counts of involuntary manslaughter. He was flying a military jet near Aviano, Italy when it sliced through the cables supporting a ski gondola, sending it crashing to the ground.

It has been one year since the ski gondola tragedy. Marine pilot Richard Ashby is the focus of a military trial at Camp Lejuene.

Some major decisions marked the first day of his court martial.

Everything from the First Amendment to the next court martial was brought up Thursday. Many people doubt this case will end with a conviction.

Even though there are doubts about a conviction, Ashby still has some explaining to do.

Why was his plane flying 600 feet below the altitude limit when it struck the gondola cable, killing 20 people?

"Mistakes were made, and that is obvious. Otherwise, that would not have happened, but they weren't all our mistakes," said Ashby during an interview with "60 Minutes."

Prosecutors wanted to subpoena outtakes, notes and off-tape comments from that interview. But citing the First Amendment, the judge threw out that request.

It is Ashby's court martial, but his navigator, Joseph Schweitzer, also appeared. The military judge said if it were his decision, he would dismiss the charges against the navigator.

Schweitzer's attorney says he will use the judge's statement in the future.

"It's concerned with justice and the appearance of justice, because if that is done, with the lack of evidence there is and will be, we are very hopeful that the charges will be dismissed," said defense attorney Dave Beck.

Victims' relatives are caught in the middle of the military legal battle. Many will be allowed to testify if a sentencing phase is necessary.

"What the law calls victim impact evidence. In other words, what this tragedy has done to their lives. So, they will be allowed to be called to the stand and testify to that," said Maj. Scott Jack, a Camp Lejeune spokesman.

A year has done little to easy the families' pain.

"What they did was just like a bunch of American boys who are somewhere in another country and think they are playing a game with a joystick," said Saskia van den Heede, victim's sister.

Many of those victims' family members are expected to come to Camp Lejuene this weekend. Starting Monday, they will be put in different rooms, and through interpreters, they will be able to watch the proceedings.

The proceedings against Ashby are expected to last about 2 and a half weeks.