Michigan has four different categories of criminal sexual conduct categories:

• Section 750.520b Section Criminal sexual conduct in the first degree; felony; consecutive
  terms.
  A defendant can be convicted of this crime if the prosecution can prove beyond a reasonable doubt that the defendant “engaged in sexual penetration with another person and if any of the following circumstances exists:
• That other person is under 13 years of age
• That other person is at least 13 but less than 16 years of age – and other statutory conditions apply such as that the defendant lived in the same household as the victim, the defendant was related to the victim by “blood or affinity to the fourth degree,” the defendant was in a position of authority over the victim, and many other conditions.
• Many other conditions such as that the defendant committed another felony or used a weapon.

A conviction of this category of criminal sexual conduct can result in life imprisonment.

• Section 750.520c Section Criminal sexual conduct in the second degree; felony.
  This offense generally includes many of the same elements as criminal sexual conduct in the first degree. A key difference is that first-degree sexual conduct involves sexual penetration while this category of offense involves sexual contact.

Sexual contact is defined as:
“The intentional touching of the victim’s or actor’s intimate parts or the intentional touching of the clothing covering the immediate area of the victim’s or actor’s intimate parts, if that intentional touching can reasonably be construed as being for the purpose of sexual arousal or gratification, done for a sexual purpose, or in a sexual manner for” revenge, to inflict humiliation, our out of anger

A conviction can result in up to fifteen years of prison time and being monitored for a lifetime.

• Section 750.520d Section Criminal sexual conduct in the third degree; felony.

This offense involves sexual penetration with another person if certain conditions exist such as:

• “That other person is at least 13 years of age and under 16 years of age.”
• “Force or coercion is used to accomplish the sexual penetration.”
• “The actor [defendant] knows or has reason to know that the victim is mentally incapable, mentally incapacitated, or physically helpless.”
• Many other conditions.

A conviction can result in up to fifteen years of prison time.

• Section 750.520e Section Criminal sexual conduct in the fourth degree; misdemeanor.

This offense involves sexual contact provided specific statutory conditions apply. A conviction can result in up to two years in prison.

The key factors that differentiate these offenses include the age of the other person, whether there is sexual penetration or sexual contact, the relationship between the accuser and the accused, and whether consent was given.

Generally, the key age is that of the accuser, not the defendant. A 17-year-old who has sex with a 15-year-old can be charged with a felony sex crime.