Party-appointed and court-appointed expert: differences and when each is used
Both produce the same type of report with identical methodology; what changes is who appoints them and at which stage of the dispute they intervene.
In a construction dispute two figures are often confused: the party-appointed expert and the court-appointed expert. The report methodology is the same; what changes is who commissions it and at which stage of the proceedings it intervenes.
The party-appointed expert
Commissioned directly by one of the parties —or its lawyer— to investigate the technical reality of the facts and support its position. It is fully valid as evidence under the Civil Procedure Act (LEC, arts. 335 ff.). It is used before a claim to assess the strength of the case, during pre-litigation negotiation, or as expert evidence at trial.
The court-appointed expert
Appointed by the court, usually by lot among those registered on the official Ministry of Justice list, or by agreement of the parties (LEC art. 339). Its distinctive feature is accredited impartiality. It must ratify the report orally before the judge and submit to cross-examination by both lawyers (LEC art. 347).
When each is appropriate
The party expert is the instrument to build your position: it brings initiative and control. The court expert brings the weight of institutional neutrality. In many disputes they coexist.
Frequently asked questions
Is a party report worth less for not being "impartial"?
No. The LEC recognises it as expert evidence. The judge weighs its evidential force by the rigour of the work, not by who commissioned it.
Can the same expert act as party and court expert?
In different proceedings, yes. In the same matter, the role is set by who appoints them.
Which is more expensive?
Fees depend on the complexity of the case, not on the figure.
