A Pentagon decision to allow the sale of Playboy and Penthouse magazines on military bases has appalled US religious groups, which insist it is illegal.

After dozens of anti-pornography groups complained to Robert Gates, the US Defence Secretary, over the sale of magazines and videos, a Pentagon board reviewed the contents of Penthouse and Playboy and decided that they were not sexually explicit.

The review board was asked to determine whether hundreds of pornographic publications breached the Military Honour and Decency Act of 1996, which bars shops on military bases from selling “sexually explicit material”.

The board decided that because the majority of each title’s contents dealt with advertising and non-pornographic material, then “based on the totality of each magazine’s content, they were not sexually explicit”. The Pentagon thus allowed the sale of titles including Celebrity Skin, Penthouse, Playboy, Playboy’s College Girls, Playboy’s Lingerie and Nude.

It banned from military shops several videos, including Girls’ Night In and Blonde and Beyond. The Pentagon said that about 67 per cent of the 473 titles reviewed had been banned.

A spokeswoman for Roscoe Bartlett, the Republican congressman who sponsored the 1996 law, told The Times that military bases were enclosed environments where families and children also lived. The base shop was often the only place for spouses, children and soldiers to buy things.

She added: “These sexually explicit magazines are treating women as sexual objects, and it is demeaning to female soldiers.”

She said that pornography increased the risk of sexual harassment and abuse of female soldiers.

Pat Trueman, the head of the Alliance Defence Fund, said that he, along with other family values groups, was overseeing an e-mail campaign to two million Americans asking them to lobby their congressmen against the Pentagon decision.

Mr Trueman told The Times: “What they are trying to do is to ban the hardest-core pornography, but allow the softer titles. That’s not obeying the law. The law says ‘sexually explicit’.”

The 1996 Act defines sexually explicit film or printed matter as “the dominant theme of which depicts or describes nudity” or sexual activities “in a lascivious way”. The Act was challenged under the US Constitution’s free-speech provisions but was upheld by an appeals court in 2002. The American Civil Liberties Union takes a different view from Mr Trueman. One member said it was absurd that the US asked soldiers to risk their lives to defend the Constitution, but there were bans on what they could read.

On the Alliance Defence Fund’s website many bloggers also defended pornography. “Hundreds of thousands of men: not allowed to be gay; expected to remain faithful to their wives. And you don’t allow porn?” said one.

Another wrote: “Porn is essential to release pent-up manhood.”

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