London - Children have a sense of justice from the age of only one and expect to see wrongdoers punished by those in charge, researchers claim.
Toddlers aged 16 to 18 months expect leaders such as parents and teachers to act when someone breaks the rules, the study of 120 children suggests.
Researchers in the US tested toddlers’ reactions using a teddy bear puppet show where a "wrongdoer" bear took all the toys.
When the "leader" bear failed to punish this, the children stared at the scene for longer – which they do when they see something unexpected. But when the leader intervened to give a toy to the bear that had missed out, the children looked away nine seconds sooner, showing events had proceeded as they thought they should.
Professor Renee Baillargeon, who led the study from the University of Illinois, said the infants’ reaction showed they "expected the leader to right the wrong".
Experts believe children are hardwired to expect leaders to administer justice, probably a throwback to early humanity when working together was key to survival.
The study, published in the journal Proceedings of the National Academy of Sciences, concludes: "By the second year of life, infants already ascribe unique responsibilities to leaders."