Inspired by Piaget's theory of moral development in children, which took a more structured approach, proposing social-cognitive and social-emotional perspectives to explain where morals come from
Piaget's theory of moral development

Proposed that until the age of 10, morals are largely concerned about obeying authority and will develop from the age of 10 into adolescence to fully mature
Kohlberg was inspired by the structural approach taken by Piaget

However argued that it had flaws
Kohlberg's theory of moral development

Proposed that moral development is a more gradual process that extends into early adulthood
Kohlberg's theory of moral development

1. 3-level, 6-stage sequence
2. Pre-conventional orientations (e.g. punish and obedience orientation which places emphasis on the self to define morals)
3. Post-conventional orientations that see that rules are not always set in stone for every situation
Kohlberg devised a longitudinal study to demonstrate the sequence of moral development in action
Kohlberg's Primary Study

To investigate moral development throughout adolescence and into early adulthood in relation to Kohlberg's sequence
Kohlberg's Primary sample

75 American boys aged 10-16 (22-28 at the end of the study)
Dilemmas for different age groups
Aged 10: 'Is it better to save the life of 1 important person or a lot of unimportant people'
Aged 13+: 'Should the doctor 'mercy kill' a fatally ill woman requesting death because of her pain'
Findings from Kohlberg's Primary Study
Moral development followed a fixed-order, 3-level, 6-stage sequence
Majority displayed moral reasoning of a single stage each time they partook
Some participants had not yet reached the final stage of the sequence by the end of the study
When confronted with the views of a child one stage further than themselves, participants seemed to prefer these views and moved forward
Aim of Kohlberg's Cross-Cultural study
To assess the extent to which Kohlberg's sequence is appropriate in a range of cultural contexts
Sample of Kohlberg's Cross-Cultural Study
Samples of boys from: Great Britain, Canada, Taiwan, Mexico, and Turkey ; varying in age
Procedure of Kohlberg's Cross-Sectional Snapshot Study
1. Completed the same moral dilemmas task as the main sample but only once
2. Dilemmas matched with participants' culture to control for response bias
Dilemma for boys aged 10-13 in Taiwan
A man's wife is starving to death but the store owner won't give the man any food unless he can pay, which he can't. Should he break in and steal some food? Why?
Kohlberg's Cross-Cultural Study Findings
Taiwanese boys aged 10-13 tended to give responses categoric of the 2nd stage
Stage 5 reasoning was more prevalent in 16 yos from America than those from Mexico and Taiwan
Middle-class children were found to be more advanced in moral judgement than lower-class children
No important differences were found in the development of moral reasoning amongst different religions
Kohlberg's Study Conclusions

There is an invariant developmental sequence that we follow to develop our moral compass
Each stage of moral development occurs one at a time and always in the same order
The sequence was not significantly affected by social, cultural, or religious conditions, only the rate at which individuals progress through it
Punishment and Obedience Orientation 

Avoidingpunishment defines the morally correct way to act
InstrumentalRelativist Orientation 

Rewardedbehaviours defines the morally correct way to act