The fifth aliyah continues judicial matters, including not taking a bribe, because the Torah says that a bribe blinds those that have sight.
Rashi explains an interesting judicial law: if someone is acquitted, and as he's leaving the court someone runs up and says they have evidence against him, we should ignore the evidence and not return to court. But if a person is found guilty and is leaving the court and someone runs up and says they have evidence in favor of him, we should return him to court to hear the evidence.
The mitzvah of the Shmittah year is explained: wherein for six years we should work and harvest the land but in the seventh year let the land rest.
The Shabbos is explained as six days we shall do our work but on the seventh day we, our cattle, our servants, and the stranger within our gates shall rest.
This aliyah says we shouldn't mention the name of other gods. Rashi says that this includes giving street directions by mentioning churches as landmarks.
The three festivals of Pesach, Shavous, and Succos are given here.
We are not allowed to cook meat with milk. Rashi says this matter is mentioned three times in the Torah to teach three things about milk and meat: that we can't eat them together, we can't cook them together, and we can't even benefit from them combined (like selling it or giving it to a pet, even if we didn't cook it or eat it ourselves).