I cannot find a Tipitaka reference for the five dhammatā, only for dhammaniyāmatā: SN12.20
There it is stated:
“Katamo ca, bhikkhave, paṭiccasamuppādo? Jātipaccayā, bhikkhave, jarāmaraṇaṁ. Uppādā vā tathāgatānaṁ anuppādā vā tathāgatānaṁ, ṭhitāva sā dhātu dhammaṭṭhitatā dhammaniyāmatā idappaccayatā. …”
So it seems dhammaniyāmatā is about paṭiccasamuppādo or how rebirth works via the akusala mula PS.
In the post What is Kamma? – Is Everything Determined by Kamma? it is said:
“3. First of all, there are actions by individuals that lead to harmful consequences right away. If one jumps from a tall building, one is bound to get hurt or worse. That is a result of dhamma niyama (law of gravitation is a dhamma niyama,) which is cause and effect. …”
But I think this is utu niyama, a physical law about rupa.
Can you explain the difference between bija niyama and kamma niyama?