Mayor Williams gives himself more power than provided by law

There is an ongoing parking debate in the nation's capitol. Many city officials feel they don't have to enforce the law if they don't want to. Mayor Anthony Williams is the lastest to make such an assertation:

There's a zone of discretion for the executive...especially when it comes to something broad and systematic. I think it'd be wrong for me to say 'I'm walking down the street and I'm going to give you a parking ticket that I won't give you.' But as a matter of broad policy it's a different question.

So, the Mayor says he has a type of discretionary authority. Well, I would disagree. At the state level, legislative bodies do give governors the right to "fill in the details of legislation." The state executive uses his or her ordinance making power which is a type a of dicretionary authority but that is clearly limited to areas where the legislative body has given the executive such power.

In addition, in the wake of a natural disaster such as a flood or tornado, a mayor may declare an official state of emergency that empowers him or her to issue binding rules of behavior for a limited period of time. A curfew ordering persons to be off the street is an example of this. Although such orders are discretionary and the law of the land, they are limited, unusual, and termporary.

From what I can tell, neither the U.S. Congress or the D.C. City Council has given Mayor Williams any discretionary power when it comes to parking enforcement. His role is clear cut and defined not only by the law, but what the common law limits executive authorities to.