Lisbeth Palme points at Christer Pettersson
More than 100 persons that prior 2003 had been convicted of serious crimes has since been released and acquitted especially due to lack of DNA evidence. Incorrect witness testimonies have caused more than 75 per cent of these arrests. 
It is strange but it has been discovered that the witnesses that were wrong, which could be proved later on by watching video tapes from the line-ups, often expressed a tremendous confidence when they blamed an innocent person.
It is a fact that witnesses only realize after a crime has been committed and the perpetrator is on the run. The witness-psychologist Elisabeth Loftus has made the discovery, that if there are weapons involved in a crime the chances of the witnesses identifying the person holding the weapon are reduced. This is called the ‘weapon-focus-effect’: The witness focuses on the weapon because it is dangerous hence pays less attention to the perpetrators face. 
This is in line with fact that Lisbeth Palme only realize that Olof Palme is shot when the perpetrator is running away. She then notices the witness Anders B and thinks he is the perpetrator.
Another study shows that witnesses that are emotionally affected notices less and disregards little details. 
The fact that Lisbeth Palme was under tremendous emotional stress after the killing was understandable. The witness P.W.  witnessed her “giggle” right after the murder, which is why he told her “I suppose there is nothing to laugh at here”.
Lisbeth Palme was therefore due to the emotional stress probably the most unreliable witness on the entire crime scene.
We know from witness line-ups that Lisbeth Palme said that “it was clear who was alcoholic”. 
It was unfortunate that Lisbeth Palme did not allow Christer Pettersson’s defence attorney presence at the line-up. This is explains why we don’t know if Lisbeth Palme got her testimony confirmed. We assume she did. The witness-psychologist tells that the witnesses that get a confirmation are much more convincing in the court that the witnesses that don’t get this confirmation.
Lisbeth Palme makes several comparisons between Pettersson and to others in the line-up, number 9 and number 11, before she rules out the others and point at Christer Pettersson. It is worth noting that according to witness-psychology, it has been noticed that witnesses that makes these kind of comparisons and don’t point out a specific person in the line-up are making far more mistakes and more often point out a wrong person .
It is not over yet. In some police districts the witness line-ups are based on very insufficient evidence whilst other places it only takes place when the police have strong evidence against a suspect.
The districts where the police perform a line-up based on the slightest hunch there are nine times as many innocent being accused for crimes they didn’t commit compared to where the police do their work properly before a line-up.
When Christer Pettersson was placed in the line-up there was no evidence or leads at all.
 Cf. ’Eyewitness Testimony’, p. 278.
 Ibid., p. 282.
 Same place.
 Cf. from the police interrogation of P.W. on the 27th of March. 1986.
 Cf. from the written note from the line-up on the 14th of December 1988.
It is signed by the prosecutors Jörgen Almblad and Solveig Riberdahl.
 Cf. ’Eyewitness Testimony’, p. 283.
 Ibid., p. 284.
 Ibid., p. 290.