As I have already posted...Alan Pike was called to attest to kates suffering...did amarals team call any experts to contest his evidence...no..it would have been a waste of time.
In order to answer this question, you have to know how a libel trial works. In Portugal, the main objective of the court is to find the truth not to convict someone. For example, in the USA, the prosecutor's goal is to convict the defendent, that's all, they are not interested in finding the truth of what actually happened.
In the pretrial meetings between the lawyers and the judge, questions are drawn up and which must be answered in order for the judge to come to his/her verdict. Then the lawyers must then find witnesses who can answer these questions. One question could be "Did the amount of information coming in to the PJ diminish after the release of the book?" Then the lawyer for the defense calls someone, obviously from the police, who can answer that question. In the questioning and the cross examination, the lawyers are not allowed to deviate from the object of this question. If they do so, the judge or the other lawyers can call them to attention. It is very rigid how a court hearing is carried out in this country.
As for Alan Pike, one of the questions was obviously about the parents mental state and he was called by the plaintiffs because of his "qualifications" and contact with the McCanns. It is not the practice here to call other witnesses to contradict other testimonies, it is not a confrontational system. I believe, however, that in the closing arguments, the lawyers can bring up contradictions, etc.