The Internet and information technology provide the greatest challenge to modern copyright law, Ms Justice Sandra Day O'Connor told the Copyright Association in Dublin Castle yesterday.
Ms Justice Day O'Connor is a member of the US Supreme Court and spoke at the association's fifth annual lecture yesterday.
While the issue arose initially in relation to computer programmes, the question of the copyright of music and films was now posed. "While I have difficulty in accessing my e-mail, every teenager can exchange whole music tapes with his friends," she said.
The US courts now made it illegal to circumvent encryption aimed at preventing the duplication of copyrighted material available through this new technology.
The Irish and the US overlapped considerably in what they did and did not protect with their copyright law, she said. However, this was likely to change as the Irish Government brought into domestic law the EU Database Directive. This differed from US copyright law in that it took into account the moral rights of the author as well as the issue of originality.
Ms Justice Day O'Connor said she did not pretend to be an expert in copyright law. However, she was the author of a Supreme Court judgment which stated that creativity rather than "sweat of the brow" was the fundamental consideration in copyright law.
This meant, for example, that the US court rejected a claim that plagiarism of the telephone directory constituted an infringement of copyright. "We said that copyright should be protected only when there was some original content," she said.
The origins of both Irish and US law lay in the 1710 Statute of Anne, which granted authors protection of their rights over their work for 28 years, she said.
Under the US constitution, copyright was protected "to promote the useful arts", emphasising the necessity for creative content. A 1790 American statute was largely modelled on this law and remained in force until 1909. This extended the period of protection to 56 years and extended the work protected to all writings, not just maps and books.
Under the pressure of international conventions, the law was further changed in 1976, taking in literary, dramatic and musical work, motion pictures, painting and sculpture and choreography.
Ms Justice Day O'Connor said certain moral rights of authorship were recognised in American copyright law, ranging from the right to acknowledgement to the protection of work from mutilation.