You don't need to know "all the laws".
You need to know all the laws you're ENFORCING RIGHT NOW.
That's why they call it "law enforcement" and not "guess enforcement" or "whim enforcement".
Sorry but no officer knows all the laws and anyone saying he does is flatout lying. Any law enforcement officer should be enforcing ALL laws but they cannot since they do not know all the laws.
Sure, a LEO will know the basics but there are many branches of a law that changes the color of the that law.
Since so many here know CCW laws and using LA as an example such as the restaurant carry I mentioned above, the law says carry is forbidden in "Any portion of the permitted area of an establishment that has been granted a Class A-General retail permit, as defined in Part II of Chapter 1 or Part II of Chapter 2 of Title 26 of the Louisiana Revised Statutes of 1950, to sell alcoholic beverages for consumption on the premises."
Ok, that is the law on the books but what about those mentioned in Title 26 of Civil Code?
Appplee's has a Class A General Permit. So do you carry in there or just in the dining area or is carry forbidden by the law? What happens if you have to go to the bathroom and pass through their bar area since there are no walls dividing it off?
Laws are often grey and there are other laws that make some law more concise.
A better example since most know basic traffic rules. You are making a left turn and doing so under the protection of an illuminated left turn arrow. An approaching motorist ignores his red signal and hits you. Who is at fault?
According to the law in Louisiana and most other states, you violated the law. The law and court rulings have upheld that a left turning motorist has the burden of proof that, even under the arrow, you have to be sure the turn can be made in safety and without danger to persons or property. You have to check for approaching traffic, cross traffic, overtaking traffic and make sure they are stopping. You also must have proof the arrow was illuminated. A local deputy was charged in such a case after an accident and he also lost the civil suit against both he and his department.
Yet ask any officer and most will say if you have the light, you are good to go.
Also, many times, an officer will call in to find out what law applies or if any law was broken. How many times have you read where someone was arrested and charges were pending or else it was being decided what charges to apply? It is not officers making those decisions, it is District Attorneys and Judges that spent years in law school and going to seminars for Continuing Legal Education each year. Often times, an opinion comes from the State Attorney General after researchers spend hours or days going over the law books to see if a law has been broken or what the appropriate law is.
If a DA, Judge or Atty General has to research the laws, how would a police officer that was just academy trained know the laws? Are you saying that a year of academy is more informative than law school?
What is your State BAC limit for a DUI charge? I bet is is .08 but I bet few know what it is for a person carrying concealed and most officers will not unless they have ran into it before. What about if the driver is underage? Is the limit the same?
Again, any officer saying he knows the law is dangerous and lying.
Also, state laws are changed at least once every two years. This year, LA had over 700 laws enacted or changed. What officer knows what laws were changed and how the laws read?