The suspect, identified as Christian Brueckner, is on trial on two counts of rape and two counts of sexual abuse.
German prosecutors have sought 15 years in prison for a man being investigated in connection with the disappearance of British toddler Madeleine McCann.
According to local media, a 47-year-old German national known as Christian Brueckner is on trial in the state court of Brunswick in northern Germany on charges of sex crimes committed in Portugal between 2000 and 2017.
Prosecutor Ute Lindemann argued in closing arguments Wednesday that the defendant should be found guilty of two counts of rape and two counts of sexual abuse and sentenced to 15 years in prison, followed by preventive detention.
Lindemann said he should be acquitted of the third rape.
Defense attorneys plan to file their case Monday, and a ruling could come Tuesday.
The suspect is currently serving a seven-year sentence in Germany for a sexual assault committed in Portugal in 2005. He has not yet been charged in the McCann case, where he is being investigated for murder.
He spent several years in Portugal, including at the resort of Praia da Luz when the British toddler went missing in 2007. He denied any involvement in her disappearance in Portugal.
Brueckner’s attorney said in February that his client would not respond to the charges but that he expected a not guilty verdict. There is no formal defense in the German legal system, and there is no obligation for the defendant to respond.
Last July, the court dismissed arrest warrants in key cases currently on trial, citing a lack of “urgent charges” against the defendants. However, he is currently serving his sentence and is in prison.