Final answer:
In criminal law, the needed standard to prove a violation is 'proof beyond a reasonable doubt', which means the evidence presented must leave no doubt of the defendant's guilt.
Step-by-step explanation:
The weight of the evidence required to prove a criminal law violation is known as proof beyond a reasonable doubt. This is the highest standard of proof in the legal system and signifies that there must be no doubt in the minds of the jury or judge regarding the defendant's guilt for the crime they are accused of. It is a much more stringent requirement than what is needed in civil cases, where only a preponderance of the evidence is necessary - meaning the evidence must simply weigh more in favor of the plaintiff's case. The concept of proof beyond a reasonable doubt is critical because, in a criminal trial, the defendant stands to lose their liberty and possibly face severe penalties such as imprisonment or even death.