Further refinements to these definitions have resulted in categories such as copyleft and permissive. There are three parenting styles that lead to child neglect&colon; authoritarian, permissive, and disengaged styles. They also tend to have permissive sexual attitudes. Missouri's alcohol laws are among the most permissive in the United States. MUMPS scoping rules are more permissive than other modern languages. Utah's firearm laws are some of the more permissive in the United States. Congress severely condemned Richardson's permissive manner. Montana has some of the most permissive gun laws in the United States. The strategy involved depicting Democratic candidates as permissive liberals. It is released under the permissive BSD 3-clause license. Adler's implementation was released under the terms of the similarly permissive Apache license. Software under a permissive license can later be made proprietary. It is published as free software under the terms of a permissive free software license. D takes a permissive but realistic approach to interoperation with C++ code. Their view is that this permissive approach is more free.