I don't know about Portugal, but it's not the case in the UK;
A witness statement is your written or video recorded account of what happened to you. A police officer will ask you questions and write down what you have said. You will be asked to read it and sign it with your name. When you sign a witness statement you are saying that you agree the statement is a true account of your experience. Your witness statement may be used as evidence in court.
https://www.cps.gov.uk/victims_witnesses/reporting_a_crime/telling_police.html
The statements taken in Portugal are not verbatim and are third party summaries which a reading of any will verify.
**snipped from
Witness statement of Gerald Patrick McCann, on the 10th of May 2007They bathed the children, the deponent having left at 18H00 for a tennis game only for men, which was attended by: DAN, the tennis instructor; JULIAN, with whom he had played tennis several times; and CURTIS, with whom he had also played before.
During the afternoon of that day, the rest of the group, including the children, were at the beach, having returned at 18H30, the time at which he saw DAVID PAYNE next to the tennis court. DAVID went to visit KATE and the children and returned close to 19H00, trying to convince the deponent to continue to play tennis, which he refused, as he had already been plying for about an hour and had to go back to his wife. Nevertheless, RUSSEL, DAVID and MATHEW stayed to play..