Like security guards, crime-fighting technologies should be implemented as a result of either or both of the following grounds:
(a) A legal duty to install technological devices may exist because the risk of shootings or other violent crimes on church property is highly foreseeable based on the following factors:
- Whether any criminal conduct previously occurred on or near the property;
- How recently and how often similar crimes occurred;
- How similar the previous crimes were to the conduct in question; and
- What publicity was given the previous crimes to indicate that the church knew or should have known about them?
(b) The use of one or more technological devices is deemed necessary to further a church's theological and biblical principles, whether or not legally required.
In evaluating the feasibility of various technologies to prevent or reduce the risk of shootings in public schools, the United States Department of Justice noted that the effectiveness, affordability, and acceptability of each technology must be considered. To illustrate, many church leaders would regard metal detectors at church entrances to be unacceptable, even if affordable and effective, because they are incompatible with the concept of "sanctuary" and are at odds with biblical assurances of providence and divine protection. For many smaller churches, such devices would be unaffordable.