The yrast and near-yrast level scheme of light neutron-rich 143 La (Z=57, N=86) is reinvestigated and expanded and that of 144 La (N=87) is proposed for the first time by measuring prompt γ rays from the spontaneous fission of 252 Cf at Gammasphere. Spins/parities are assigned to the lowest-lying levels of 143,144 La based on the early studies of β− decay, and the assignments for high-spin levels of 143,144 La are made by measuring internal conversion coefficients and following the level systematics of the neighboring heavier La isotopes and even–even Ba and Ce nuclei. The B(E1)/B(E2) ratios, energy displacements δE(I) and rotational frequency ratios ω−(I)/ω+(I) of the new parity-doublets of 143,144 La indicate that octupole deformations/correlations also develop in these nuclei. The band-crossings observed in a rotational frequency range of 0.31 to 0.34 MeV for the two even-parity bands in 143 La but being absent in 144 La are interpreted as due to alignment of a pair of i13/2 neutrons in 143 La.