A sentence of 30 years in prison for obstructing an investigation is excessive, especially when compared to the "base offense level" of Involuntary Manslaughter (section 2A1.4 found here[0]) being between 12 and 22, roughly translating to between 10 and 51 months in prison[1] (assuming no prior felony convictions).
Not 360 months, which is the length of this sentence.
0 - https://www.ussc.gov/sites/default/files/pdf/guidelines-manu...
1 - https://www.ussc.gov/sites/default/files/pdf/guidelines-manu...