In a damning indictment of the actions by the French press, William said in his statement that the photographs “reminded us of the harassment that led to the death of my mother, Diana Princess of Wales."
The six defendants on trial include paparazzi photographers and editors of Closer, the magazine that published the topless images of the Duchess of Cambridge.
The photographs allegedly were shot with a telephoto lens from several miles away while William, now 34, and Kate, now 35, vacationed at Lord Linley's private chateau in Provence, France. The most intimate shots showed Kate bathing topless on a private terrace on the estate and William putting sunscreen on his wife. The photographs were published in Closer magazine and its sister publication, the Italian magazine Chi, and several other outlets as well as online.
French authorities banned further use of the photographs and launched an investigation into how they were obtained.
Veil read a written statement from William in court.
"In September 2012, my wife and I thought that we could go to France for a few days in a secluded villa owned by a member of my family, and thus enjoy our privacy," the statement said. "We know France and the French and we know that they are, in principle, respectful of private life, including that of their guests. The clandestine way in which these photographs were taken was particularly shocking to us as it breached our privacy."
The lawyers for William and Kate also demanded fines in the amount of 1.5 million euros, a large sum by European standards.
The photographers have denied taking the photos. French authorities say they tracked the photographers down by tracing hotel and phone records of those who were staying near the chateau where William and Kate vacationed.
The defense barrister for Closer magazine, Paul Albert Iweins, spoke to the press at the conclusion of the hearing, saying that both readers and the royal family liked the article.
"It was an extremely flattering representation of the couple, so I don't really understand the bad lawsuit against us," Iweins said.
Francois Blistene, who represents two of the photographers, claimed his clients were being used as scapegoats.
St. James Palace issued a statement after the photos were published in 2012, describing the incident as being "reminiscent of the worst excesses of the press and paparazzi during the life of Diana, Princess of Wales."
In the last few years, Kensington Palace has taken a much more aggressive posture toward the media.
Kensington Palace declined to comment to ABC News on Tuesday's trial involving William and Kate, saying it does not comment on ongoing court cases.
A verdict is expected July 4.