In other words, they devised a theory which would fit their pre-conceived conclusion. That theory was disbelieved by two members of the commission and by LBJ himself during a briefing call by Senator Russell who was personally reporting the progress of the commission to LBJ in phone calls which were taped. LBJ was sharing his "concerns" about serious issues and Russell would assure him that the commission was doing the right thing. LBJ always believed it was a conspiracy and he was determined that it would not be divulged to the public because we may press for a war as retaliation. Part of those conversations were on TV this week.
CBS has a tape of the commission doing just that and viewing the pathway of the car including the view though the tree(s). Subsequently, the city of Dallas work crews trimmed the tress back.
This fact was repeated on PBS this week: American Experience Oswald's Ghost. I didn't make it up. I saw the first broadcast on CBS and saw the film again this week.
The rest of the story is in #89.