The fourth aliyah has laws of blasphemy (against G-d, rulers, and judges), laws of sanctifying the first-born son (the pidyon haben ceremony), first of the harvest and of cattle. Also here are some laws of kashrus -- the word "trefa" appears here. The law of uttering a false report (Rashi says: also accepting a false report) and other matters of judicial process are also given here.
Here are also the laws concerning seeing your enemy's animal going astray - you should bring it back to him. Similarly, if you see your enemy's animal under a burden, you should help.