Laws and rules and Dhamma How are laws and rules in harmony with the Dhamma? How are the laws and rules we make in harmony or in conflict with the Dhamma?  How can one  best practice Dhamma while also practicing law ,enforcing law or enforcing any rules?
You can read some advice given by the Buddha in DN16 in the section entitled "Conditions of a Nation's Welfare". There are many items listed like organizing and dispersing assemblies peacefully, living according to established rules, honoring the elders, protecting women, protecting Arahats etc.

You can also read "The Edicts of King Asoka" translated by Ven. Dhammika. For e.g. this verse from The Fourteen Rock Edicts:


  I have had this Dhamma edict written so that my sons and
  great-grandsons may not consider making new conquests, or that if
  military conquests are made, that they be done with forbearance and
  light punishment, or better still, that they consider making conquest
  by Dhamma only, for that bears fruit in this world and the next. May
  all their intense devotion be given to this which has a result in this
  world and the next.


Regarding enforcing laws, King Asoka's Kalinga Rock Edicts state:


  Beloved-of-the-Gods says that the Mahamatras of Tosali who are judicial officers in the city are to be told this: I wish to see that
  everything I consider to be proper is carried out in the right way.
  And I consider instructing you to be the best way of accomplishing
  this. I have placed you over many thousands of people that you may win
  the people's affection.
  
  All men are my children. What I desire for my own children, and I desire their welfare and happiness both in this world and the next,
  that I desire for all men. You do not understand to what extent I
  desire this, and if some of you do understand, you do not understand
  the full extent of my desire.
  
  You must attend to this matter. While being completely law-abiding,
  some people are imprisoned, treated harshly and even killed without
  cause so that many people suffer. Therefore your aim should be to
  act with impartiality. It is because of these things — envy, anger,
  cruelty, hate, indifference, laziness or tiredness — that such a thing
  does not happen. Therefore your aim should be: "May these things not
  be in me." And the root of this is non-anger and patience. Those who
  are bored with the administration of justice will not be promoted;
  (those who are not) will move upwards and be promoted. Whoever among
  you understands this should say to his colleagues: "See that you do
  your duty properly. Such and such are Beloved-of-the-Gods'
  instructions." Great fruit will result from doing your duty, while
  failing in it will result in gaining neither heaven nor the king's
  pleasure. Failure in duty on your part will not please me. But done
  properly, it will win you heaven and you will be discharging your
  debts to me. ....
  
  This edict has been written for the following purpose: that the judicial officers of the city may strive to do their duty and that the
  people under them might not suffer unjust imprisonment or harsh
  treatment. To achieve this, I will send out Mahamatras every five
  years who are not harsh or cruel, but who are merciful and who can
  ascertain if the judicial officers have understood my purpose and are
  acting according to my instructions. Similarly, from Ujjayini, the
  prince will send similar persons with the same purpose without
  allowing three years to elapse. Likewise from Takhasila also. When
  these Mahamatras go on tours of inspection each year, then without
  neglecting their normal duties, they will ascertain if judicial
  officers are acting according to the king's instructions.


King Asoka's Seven Pillar Edicts talk about the hearing of petitions and the administration of justice:


  Beloved-of-the-Gods speaks thus: This Dhamma edict was written
  twenty-six years after my coronation. My Rajjukas are working among
  the people, among many hundreds of thousands of people. The hearing of
  petitions and the administration of justice has been left to them so
  that they can do their duties confidently and fearlessly and so that
  they can work for the welfare, happiness and benefit of the people in
  the country. But they should remember what causes happiness and
  sorrow, and being themselves devoted to Dhamma, they should encourage
  the people in the country (to do the same), that they may attain
  happiness in this world and the next. These Rajjukas are eager to
  serve me. They also obey other officers who know my desires, who
  instruct the Rajjukas so that they can please me. Just as a person
  feels confident having entrusted his child to an expert nurse
  thinking: "The nurse will keep my child well," even so, the Rajjukas
  have been appointed by me for the welfare and happiness of the people
  in the country.
  
  The hearing of petitions and the administration of justice have been
  left to the Rajjukas so that they can do their duties unperturbed,
  fearlessly and confidently. It is my desire that there should be
  uniformity in law and uniformity in sentencing. I even go this far, to
  grant a three-day stay for those in prison who have been tried and
  sentenced to death. During this time their relatives can make appeals
  to have the prisoners' lives spared. If there is none to appeal on
  their behalf, the prisoners can give gifts in order to make merit for
  the next world, or observe fasts. Indeed, it is my wish that in this
  way, even if a prisoner's time is limited, he can prepare for the next
  world, and that people's Dhamma practice, self-control and generosity
  may grow.