Youthful romance may never be the same again. German teenagers caught petting in cinemas or posting suggestive pictures of themselves on the internet could be prosecuted under strict new laws to be passed in the Bundestag.

Magazines for teenage girls, such as the widely read Bravo, will have to think again before publishing photo-stories of scantily clad young couples in passionate embrace, or risk landing their editors in jail for ten years. Even writers and painters will have to be careful when depicting under-age subjects in sexual situations. They too could be sent to prison.

The legislation, which is aimed at stamping out child prostitution, has drawn a storm of protest from legal experts, liberal politicians and even sex therapists. The law was due to be introduced tomorrow but the Government withdrew it at the last minute because of the scale of the opposition.

“It represents a moral rollback to the puritanism and prudishness of the 1950s,” said Jerzy Montag, a Green Party MP who is trying to rally opposition in parliament. “The State is attempting to interfere in the most intimate sphere.”

The new law reduces the minimum age at which sexual offenders can be prosecuted from 18 to 14, and raises the maximum age at which a victim is entitled to legal protection from 16 to 18. The idea is to stop the recruitment of minors as prostitutes by other minors — pimps in big cities are often 17 or younger — but the initiative is a legal minefield.

“If a 15-year-old says to a 17-year-old, ‘I'll invite you to the cinema providing we have a bit of heavy petting afterwards', then that will now be a criminal offence,” said Mr Montag. “Even if the 17-year-old says no, it will still be illegal. The mere attempt to secure sexual favours in return for payment in kind is against the new law.”

The law will put parents and other adults — such as cinema managers and teachers — in a difficult position. If they overhear a comment that suggests that a teenager is putting pressure on another teenager, or offering a reward, for sex then they have an obligation to call the police. But the crucial evidence may hinge on the slightest of nuances. “If a youth says, ‘I'll pay for the cinema and then we'll snog', that's still OK,” Mr Montag said. “But if he says, ‘I'll pay for the film and I want to snog in return', then he has broken this law.”

Christine Lambrecht, a Social Democrat MP who helped to draw up the changes, said that the real target was not fumbling teenagers on the back seat of a cinema but people trying to recruit child prostitutes.

“We're talking about a 15-year-old who says to a !7-year-old, ‘I'll buy you a designer jacket if you sleep with me',” she said. “All too often that kind of approach is the start of a recruitment process.”

Two laws are involved. The first is Article 182 of the Criminal Code, which is concerned with sexual abuse of minors and which can lead to hefty fines or up to five years in jail. The second is Article 184b, which covers the possession and distribution of child pornography. The amendments to both laws significantly broaden the age range for minors as victims and offenders. Possession of child pornography can lead to a jail sentence of between three months and ten years.

The public debate about the laws is confusing adults as well as teenagers. The law is already fuzzy about the rights of fathers who want to post pictures on the internet of their naked toddlers in the paddling pool. German courts appear to accept distribution of such pictures within the family circle, but not a broader audience.

Now a teenager who photographs a teenage couple embracing in a park will be liable for prosecution if he or she distributes the pictures broadly on the net. A teenage girl who photographs her classmate in a revealing swimsuit and then sends it to her is still just within the law, providing that both girls consent and the picture is only for personal use. As soon as the picture is sent to another friend, the law has been broken. Even the act of downloading the picture is illegal.

“This is going to lead to a wave of pointless investigations and court cases,” said Andreas Hill, a sexual researcher in Hamburg who is one of several experts pleading with the Government to drop the bills.

“They will burden the already overloaded police to such an extent that the really relevant cases slip out of view.”

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