Supporters outside the court held aloft a banner reading "Saving lives is not a crime" as the captain of the Sea-Watch 3 spoke to the media after the questioning on Thursday, AFP reported.
"I was very happy to have the opportunity today to explain all the details about the situation of the rescue," she said.
"I sincerely hope that the European Commission, now after the new election of the Parliament, will do their very best (to) prevent situations like that happening," she said in English.
"And that all the European countries will work together in the future to accept any people which the civilian fleet has rescued."
Rackete was arrested on June 29 for entering the port on the island of Lampedusa despite a veto imposed by far-right Interior Minister Matteo Salvini, and knocking a coastguard boat out of the way to land 40 migrants who were blocked at sea for over two weeks.
A judge overturned the arrest three days later, saying the 31-year old had acted to save lives.
The Sea-Watch 3 ship remains in police custody in the Sicilian port of Licata, and Rackete is still the subject of two investigations — one for entering Italian waters despite a direct order to stop, and another for aiding illegal immigration.
She was being heard on the second probe on Thursday, to explain why her crew rescued the migrants without waiting for the Libyan coastguard, which has jurisdiction over the stretch of water in which they were found.
The 31-year-old was also to be asked why she then sailed the Dutch-flagged vessel to Italy rather than a Libyan or Tunisian port.
Salvini insists that Italy's ports remain closed to people who attempt the perilous Mediterranean crossing, many of them fleeing war, poverty or repression at home.
UN human rights experts on Thursday released a statement expressing "grave concern... over the detention and criminal proceedings against Rackete".
"We urge the Italian authorities to immediately stop the criminalization of search and rescue operations".
Prosecutors in Agrigento appealed to Italy's highest court this week against the decision to drop charges against Rackete for forcibly entering Lampedusa Port, in the hope of establishing a precedent to put off other privately run ships.
A few days after the Sea-Watch drama, another charity vessel forcibly landed in Lampedusa, a scenario that is likely to recur.
Salvini's hardline stance has led to an upsurge in investigations into charity rescue vessels.
In March 2017, the Spanish vessel Open Arms was seized and its captain and head of mission were prosecuted after the crew refused to hand saved migrants over to the Libyan coastguard, which arrived at the scene during a rescue operation.
A month later a judge ordered the vessel released on the grounds that crisis-hit Libya could not be considered a safe port.
And the prosecutor's office in Catania, eastern Sicily, recently archived the case against the captain and mission head.
The same prosecutor closed a similar probe against the NGO Sea-Watch after a rescue operation in January, concluding that the crew's actions were justified.
But the Sea-Watch 3's dramatic port entry in June marked a new chapter in the war between Salvini and charity vessels.
The arrest of the dreadlocked Rackete sparked an online campaign which raised over €1.4 million ($1.57 million) in a few days to pay her legal fees and enable the German charity to continue its operations — with a new boat if necessary.
On Tuesday the parliament of Catalonia in Spain voted unanimously to honor Rackete with a Gold Medal, its highest award.
And the city of Paris announced a donation of €100,000 to Sea-Watch, as well as a medal for Rackete and Pia Klemp, another German captain prosecuted in Italy.
Salvini has stepped up his attacks on the rescue charities, which he has accused of aiding people-smugglers, while calling Rackete a "bigmouth" and a "criminal".
Rackete filed a complaint last week for defamation and incitement to violence, noting that Salvini's hostile messages on social networks have prompted an outpouring of sexist, violent and threatening comments from users.