DeparturismParr 2025. is an anti-abortion libertarian philosophy developed by American philosopher Sean Parr which argues, contrary to evictionism,Cesario 2019. that the lethal removal of an unwanted embryo or fetus ought to be legally impermissible (except in cases where the pregnancy jeopardizes the life of the mother).See Parr 2020, 67: "The degree of severity necessary in the treatment of a fetus (wanted or unwanted) whose occupation of the womb seriously endangers the life of the mother would be more than is appropriate, nay, more than is compatible with libertarianism, in dealing with a fetus whose occupation represents a mere trespass."
Unlike the traditional pro-life vs. pro-choice dichotomy, both departurism and its libertarian counterpoint, evictionism
Commonalities with evictionism
Both departurism and evictionism acknowledge "the complex ethical questions surrounding abortion, particularly the tension between fetal moral status and a pregnant person's bodily autonomy."Morales 2025, para. 6. Regarding the moral status of fetal life, both frameworks view the fetus as a distinct, living human being and, further, admit his personhood.Block & Whitehead 2005, 17: "The fetus is an alive human being from day one onward, with all the rights pertaining to any other member of the species."
Further, both frameworks recognize the mother's autonomy over her own body. To this end, there are two aspects of these theories that make them uniquely libertarian: They view the abortion issue through the lens of property rights,Block & Whitehead 2005, 1: "We advocate a liberty and private property rights approach to the issue of abortion." allowing that an unwanted fetus is to a mother what a trespasser is to the owner of the property in question. They conceptually separate abortion into (a) the removal of the child from the womb and (b) the resultant death of the child. Abortion, thus, is understood as lethal eviction.Block 2010, 1-2. Both theories generally view the act of eviction as broadly justifiable on its own,Parr 2020, 65-66: "[Departurism] will permit the non-lethal eviction of a fetus for the purpose of the reasonable upholding of the mother's property rights." while justification for abortion in its entirety is more limited and specific, varying for different reasons and to different extents.Morales 2025, para. 4: "Unlike absolutist moral positions, these frameworks allow for the decoupling of pregnancy termination from fetal death, thus transforming the abortion debate from an intractable moral impasse into a solvable regulatory challenge."
Moreover, both theories argue that the fetus lacks mens rea in his occupation of the mother's womb, so the mother's treatment of the fetus must follow the principle of gentleness.Block, Kinsella & Whitehead 2006, 945: "The woman who no longer wishes to 'house' the fetus within her body is under no obligation to do so. She may evict this interloper from her 'premises.' She must do so in the gentlest manner possible, for the trespasser in this case is certainly not guilty of mens rea."Block 2010, 3: [Gentleness is] "a basic axiom of libertarianism."
Gentleness
Gentleness is an ex ante element of law—similar to the ex post element, proportionality—which states that if the victim of an invasion intends to halt it while it is occurring, they must only use the least severe measures necessary to do so. Failing to use the gentlest means possible to end non-criminal aggression, places the victim "at risk of falling on the wrong side of the non-aggression principle,"Parr 2020, 60-61. violating it "to a far greater extent than is the trespasser."Block 2011A, 3. Because all fetuses "are equally innocent,"Block 2011A, 8. this attempt to curtail property owners from dealing with such trespassers "more severely than libertarian punishment theory allows"Block 2013, 132. is applicable to unwanted fetuses who are the result of rape no less than those whom are consensually conceived.See Parr 2025, v: "Departurism... protects all chldren from unnecessary abortion—even those whom are the result of rape."
Conflict with evictionism
Where departurism and evictionism differ is in their understanding of what gentleness ought to look like when it is properly applied to situations of trespass within the womb.
The evictionist view is that the mother may not directly kill the unwanted child (e.g., initiate a medical abortion,Block & Whitehead 2005, 25: "RU 486… which kills and then flushes out the fetus, [should not] be legal." non-lethally evict the child and then kill him, Block & Whitehead 2005, 27: “The pregnant mother... may evict, but not evict and then murder.” etc.), but she may indirectly do so by evicting him from her premises during a time in which he is non-viable outside the womb.Morales 2025, para. 13: "In Block’s account, abortion is only justifiable when the fetus is non-viable and its death is an unavoidable consequence of eviction." This lethal eviction however, if it's to be in accord with gentleness, must proceed only after the relevant authoritiesBlock 2011A, 2: “E.g, the hospital, the church or synagogue, the orphanage.” have been notified to see if they are able and willing to prevent this removal from becoming fatal.Block 2011A, 2: "The 'gentlest manner possible' in this case requires that the mother notify the authorities to see if they will take over responsibilities for keeping alive this very young human being. However, if the 'gentlest manner possible' implies the death of this very young human being, then so be it: the mother still has that right."
Departurism, likewise, holds that the mother may evictParr 2011, 14: “The notion of eviction as the gentlest means possible is not, per se, incongruous with libertarianism.” but not directly kill the trespassing fetus, but, contrary to evictionism, neither may she kill him by eviction. The mother, if her actions are to conform to gentleness, must allow for the continued departure of the trespasser until such time that eviction no longer entails his death.Morales 2025, para. 18: "Departurists argue that a fetus... must be permitted to complete [the gestational] process unless removal would be non-lethal or necessary to prevent a direct and imminent threat to the pregnant person's life." That is, "it is only the lethal (or otherwise debilitating) eviction of a fetus during a normal pregnancy that departurism views as discordant with gentleness and, thus, a violation of the NAP."Parr 2020, 65.
Because the requirements of both views (evictionism's notification and departurism's continued departure) are said to find their justification in gentleness, it is the view whose requirement best conforms to this principle that should be preferable on libertarian grounds.
The departurist argument
The departurist argument is an attempt to take into account the unique characteristics of an unwanted pregnancy in order to avoid unnuanced comparisons which liken womb-aged children to ordinary, criminal trespassers; and show the NAP-preserving gentleness principleBlock 2011B, 5: "From whence, then, does [gentleness] spring? I contend that it stems from the [NAP]." to be the lens through which libertarians properly discern this issue.
First, the departurist argument compares two situations, S1 and S2.
S1 represents the situation of a trespasser who is (a) unable to engage in human action and (b) leaving the premises of the property owner,Parr 2013, 113: “A non-criminal aggressor need not be capable of human action in order to be the object of a departure-eliciting process — his departure may be the result of something outside of his sphere of control.” while (c) not endangering the life of the same, and where (d) the eviction of this trespasser will result in his death. S2 represents the situation of an unwanted fetus in the uterus of his mother.
Departurism claims that these situations are relevantly similar to each other and therefore cannot be treated differently. That is, the requirement of practical consistency dictates that the same course of action is appropriate in both situations.See Walton 2008, 306.
Second, the departurist argument describes a course of action, A.
A represents the course of action in which the property owner allows for the trespasser to continue his departure until such time that eviction will not necessitate his death.
Departurism claims that this course of action stops the trespass in a comparatively less harmful manner than does the course of action advanced by evictionism (e.g., it doesn't entail that the inadvertent aggressor be subjected to unjustifiable life-taking or NAP-violating violence).See Parr 2020, 73-74. That is, the principle of gentleness dictates that this course of action is the correct, libertarian one in either case.
The course of action that libertarian legal theory ought to endorse in S1 is A. S2 is relevantly similar to S1. Therefore, the course of action that libertarian legal theory ought to endorse in S2 is A.See Parr 2020, 68.
Premise one
Departurism illustrates a potential expression of S1 which includes all of its relevant conditions (a-d). This illustration posits a property, owned by M and on which F is trespassing, which abuts a cliff on its southern border. F, whose mental state or capacity is such that he is incapable of knowing that he is trespassing,Parr 2020, 68: “We can add, also, that [M] knows (or... can be reasonably expected to know) that [F] is incapable of purposeful behavior.” is travelling along this cliffside from west to east and off of M's property (that is, unwitting F happens to be vacating the premises).Parr 2011, 7: “It may be claimed of gentleness that A is not applicable to it because, in allowing for the continued... departure of the trespasser, the property owner is not acting—and action is required of the property owner if he is to treat the perpetrator in the gentlest manner possible. This objection, however, cannot be said to be a valid one [because].... action is not only doing but no less omitting to do what possibly could be done. So, in allowing for A, the owner of the property in question... exhibits his capacity for action by not evicting unto death the morally innocent trespasser on his premises." Importantly, there is nothing about F's trespass which is seriously endangering M's life.Parr 2020, 72: “We might... posit that F is further aggressing against M’s property by instinctively eating some of the garden vegetables as he proceeds eastward. An aggravating aggression.... [b]ut, like his current trespass, an inadvertent, property-directed one that is in the process of ending and is not justly ended sooner by the quashing of F’s innocent life." M knows that should F be pushed off the cliff while on the western end of the premises (the black area), F will certainly die due to the severe height of the fall. Further, M is aware that a fall from the eastern end of the premises (the white area) will not prove fatal for F due to the negligible distance from the cliffside to ground below. A fall from in between these ends (the gray area) may or may not be deadly. According to departurism,