The statement followed a request by six journalists for an investigation into a media report that their telephone calls had been monitored by the secret police.
PEN Centre President Zvonko Makovic said that "the illegal practice of endangering the freedom of journalists, which means the freedom of information and the freedom of expression, is inappropriate to a civilised society and is totally alien to the European community where Croatia sees its place."
Makovic said that "it is necessary to change the habits redolent of the past and dangerous times" in order for Croatia to get closer to the European Union.
"Many have been inclined to believe that Croatia has evolved over the past few years in civilisation terms and that the ruling party has abandoned the habits of the past when the freedom of speech was reduced and journalists were attacked with accusations reminiscent of the totalitarian regimes of last century," the president of the PEN Centre said.
Makovic said that the latest case showed that Croatia was far from democracy and that it did not meet the criteria of the European Union.