If a woman has an abortion and goes to confession to a priest are her sins absolved? Someone recently told me that only a bishop has that authority. Please advise
The issue of abortion is complicated slightly by the fact that it carries the penalty of automatic excommunication in canon law (canon 1398). The reason for this is not punishment, rather it is to highlight and warn of the seriousness of the sin. Generally, if someone has incurred excommunication then only the local ordinary can lift it (canon 1355 §2)
In order for automatic excommunication to apply certain conditions must be met (canon 1323): person must have been at least 16 years old, must know the law and penalty, must have freely chosen the action, and must have the proper use of reason.
Someone who is forced to have an abortion or is coerced out of fear does not incur any penalty. Someone who is unaware of the penalty also cannot incur it. In such situations a priest can absolve because there is no penalty to be removed.
If someone over the age of 16 with appropriate faculties of reason freely chose an abortion knowing it would lead to automatic excommunication, such a person would have incurred automatic excommunication and such a penalty needs a bishop to lift it. However, in the dioceses of the United States the Bishops have delegated to the priests under their authority the canonical power to lift the excommunication in the sacrament of confession. So, in the USA *any *priest can lift the canonical penalty if it applies.
I have heard of Bishops in other countries doing the same, but I hesitate to try and compile a list lest I accidentally provide misinformation or leave off a country/diocese.