The apples which in nature and owned by everybody, when gathered from trees by someone by mixing labor into, becomes the apples of the laborer or theater. By that way, I mean by mixing labor on something as Locke signifies, natural right of property can be established over something which is before common. However the question is, can one use harm principle without violating Locke’s natural property right? The process of mixing effort on something is unclear.
One may exert any kind of force and work to get the property of anything and may say “1 have put my work on it” although actions may not legal, unjust, unfair and not protected by government. Another aspect is how someone can know and set apart the common and the wend property? Again he may put his effort on something which is already owned by another. The rule, first come, first served is not so determining and in practice many conflicts may occur. In both cases someone may get hurt by actions.
So in a sense, it seems harm principle is needed to be accepted by the government in order to prevent such harmful actions performed by ones who try to own something. In my opinion, in such cases putting into practice the harm principle is not a violation over property right, seems more like a limitation on behalf of mankind. Moreover, as Locke also explains everyone should not labor more than he could make use of, otherwise indirectly others may be affected by scarcity and lack of resources.
At that point again harm principle can step in, and in order to prevent someone to acquire more than what he needs, common authority may exercise power on selfish ones. In conclusion, one may say that harm principle generally can be exercised by community while not violating the natural rights but limiting it on behalf of members of the society. Because as I tried to show that without such instruments, mean harm principle, people who had bad faith in, can use natural rights in evil things.