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What Crimes May Be Merged
The rules on merger vary from state to state, and they're different when federal laws are involved, too. Also, the facts and circumstances of the case usually have an impact on whether crimes will merge. Nonetheless, there are some general rules when it comes to the merger doctrine:
Merger will likely be applied when one crime is a lesser included offense of another crime committed by the defendant. For example, the crime of theft or "larceny" usually involves the taking of someone else's property, without permission and with the intent of keeping it. Robbery includes the same conduct, but with the threat of physical force or intimidation. Theft is part of robbery, and so the two crimes merge. So, a defendant who steals a victim's purse at gun point can't be convicted of and sentenced for theft and robbery. He'll likely be convicted of and sentenced for robbery only
If each crime has different elements, or if the prosecution needs different evidence to prove each crime, merger won't apply, even if the two crimes arise from the same conduct. For instance, where an the aggravated assault charge requires proof that a defendant used a deadly weapon to cause injury, and an aggravated battery charge requires proof that he caused the victim to lose the ability to use a part of his body, the two crimes have different elements and don't merge
If one crime is completed before another, there's no merger. For example, if a defendant robs a store clerk at gunpoint and takes money from the cash register, and then he hits the clerk in the head with the gun, the crimes of armed robbery and aggravated assault don't merge
An attempt to commit a crime merges with the actual crime, once the actual crime is committed. For example, a defendant commits attempted burglary once he tries to pry open the door to house with the intention of stealing money and valuables inside it. If he actually breaks in and takes valuables, he can't be can't be convicted of sentenced for the attempt and the actual burglary (This rule varies greatly from state to state)
Conspiracy to commit a crime and the actual crime, if committed, don't merge. So, if two defendants plan out a bank robbery and then carry out that plan, each defendant can be convicted of and sentenced for the crimes of conspiracy and bank robbery
Each state may have different rules about merger, and the federal laws are different, too. Also, the facts and circumstances of your case will have a big impact on merger. Be sure to check the laws that apply to your case, and talk to an experienced criminal law attorney, to make certain that you don't lose any benefits from the merger doctrine.
Sentencing
When it comes to the sentencing phase of a criminal prosecution, the judge looks at your convictions to determine the sentence or punishment you should get. If you've been convicted of more than one crime, the sentences may be stacked or added to each other, which will lead to a harsher sentence, like longer jail time. At this point, the judge can determine