Canon 87. §1 Whenever he judges that it contributes to their spiritual welfare, the diocesan Bishop can dispense the faithful from disciplinary laws, both universal laws and those particular laws made by the supreme ecclesiastical authority for his territory or his subjects. He cannot dispense from procedural laws or from penal laws, nor from those whose dispensation is specially reserved to the Apostolic See or to some other authority.
[NB see Authentic Interpretation of canon 87 §1, 5.VII.1985]

§2 If recourse to the Holy See is difficult, and at the same time there is danger of grave harm in delay, any Ordinary can dispense from these laws, even if the dispensation is reserved to the Holy See, provided the dispensation is one which the Holy See customarily grants in the same circumstances, and without prejudice to can.
291.

§1. Episcopus dioecesanus fideles, quoties id ad eorundem spirituale bonum conferre iudicet, dispensare valet in legibus disciplinaribus tam universalibus quam particularibus pro suo territorio vel suis subditis a suprema Ecclesiae auctoritate latis, non tamen in legibus processualibus aut poenalibus, nec in iis quarum dispensatio Apostolicae Sedi aliive auctoritati specialiter reservatur.

§2. Si difficilis sit recursus ad Sanctam Sedem et simul in mora sit periculum gravis damni, Ordinarius quicumque dispensare valet in iisdem legibus, etiam si dispensatio reservatur Sanctae Sedi, dummodo agatur de dispensatione quam ipsa in iisdem adiunctis concedere solet, firmo praescripto can. 291.