Explanation:
Pros:
-At times they can have people released earlier
-Shorter sentences
-Less jail time
-Effective negotiating tool
-Lessens the amount of people within jails
-Removes the uncertain or unknowing factor within cases
Cons:
-People who are not guilty are pleading guilty for a crime they did not commit
-They may be manipulated by the legal system
-Removes the right to have a trial by jury
-Judges do not always have to listen or adhere to plea bargain agreements
-Can lead to bad investigatory treatment
I think that due to the legal system and the way it works, it is not inherently necessary but it is a good tool that can be used to smooth out trials, reduces the amounts of people in jail and close cases faster, so wasting less money on trials.