I suppose you could at least apply for a restraining order. The judge might find for your neighbor and not grant the order. If you believe there has been police misconduct, you can contact the attorney general's office and/or a private attorney who specializes in these kinds of cases.
The restraining order law has recently been modified, and this change may include the neighbor under its span.
You can also contact the police to see if the harassment reaches criminal proportions.
You may also want to consider filing a private party complaint in the district court alleging criminal harassment against your neighbor. Criminal harassment requires that your demonstrate that your neighbor knowingly engaged in a pattern of conduct or speech, or a series of acts, on at least three separate occasions, directed at you; that those actions were of a kind that would cause a reasonable person to suffer substantial emotional distress;that those actions did cause you to become seriously alarmed; and that your neighbor engaged in those actions willfully and maliciously.
At the present time you can only seek a restraining order under the general equitable powers of the Superior Court. These cases require a filing fee, service fees, and injunction fee totaling a over $400.00. There is a new Harassment Prevention Order, that will be available in the District, as well as other, courts without the fees. This law will not be effective until May 9, 2010. Check out my website and blog for more information.
As attorney Pang stated you may have the basis for a criminal complaint for criminal harassment. You should contact the local police department, and if they do not apply for a criminal complaint, you can contact the court and apply yourself.
DISCLAIMER: This answer is provided in response to a "hypothetical" question and provided for general, informational purposes and does not create an attorney/client relationship. The information presented is not legal advice and may change based additional information and research. It is recommended that you speak to an attorney to discuss your specific legal issues.