MADRID, Spain — A cartoonist and a writer were found guilty yesterday of “attacking the honor” of Crown Prince Felipe, 39, in a ruling many Spaniards saw as a setback for freedom of expression in post-Franco Spain.

The two men, whose cartoon of the heir to the throne and his wife making love was published on the front of a satirical magazine, were fined about $4,000 each.

Judge Jose Maria Vazquez Honrubia ruled that the two men “vilified the crown in the most gratuitous and unnecessary way.” He said they could serve 10 months house arrest if they refused to pay.

The public prosecutor, Miguel Angel Carballo, had demanded a fine of about $8,700 each.

Guillermo Torres, a cartoonist, and Manel Fontdevila, a writer, said the sentence was “unfair and subjective” and they planned to appeal.

In their drawing, published last July in the satirical magazine El Jueves, the prince is commenting to his wife about the socialist government’s plan to give 2,500 euros for each baby born to married couples with legal residence in Spain. Under the heading “2,500 euros a child,” the red-nosed prince says: “Have you realized that if you get pregnant … this will be the nearest thing to work I’ve done in my life!”