AUSTRALIAN juries have been so influenced by American television shows such as Law and Order they are adopting US legal terms that have no relevance in Australian courts.

Phrases such as ''Miranda rights'' and ''preponderance'' are being bandied about by jurors spending their evenings in the thrall of CSI: Miami.

In groundbreaking studies revealing low levels of jury comprehension of a judge's instructions, psychologist Professor James Ogloff said tests of people summoned for jury service in Victoria over the past five years found that when ''people explain the law, they often slipped into what they learn on television''.

''Sometimes we would find, in the responses to our survey, jurors here write things using American terminology,'' he said.

''We use terms like 'on balance of probabilities' here and Americans use 'preponderance' … people would write words like preponderance.''