I agree that knowing tax law is helpful, but there are still anomalies to be found. For example, I found a case where a slave paid tax, presumably on himself, while he was self-hired and part of an estate.

Initially when I looked at the tax list, I assumed that because he was listed, he was free. After searching through court records for manumissions at this time, I couldn't find any evidence that he was freed. Furthermore, he was listed a year later as a slave in the estate of a deceased free mulatto woman. Chances are that the executor of the estate made arrangements with him to pay his own tax, to avoid further indebtedness of the estate, but I have no other information to support this.

This same woman owned a total of four slaves at one time, a woman with two children and a man. There is no indication that the man and the woman were related to one another or to their enslaver. Furthermore, no one in this mulatto slaveowner's family or household, ever paid taxes on more than one slave at a time in any given year, from 1819 until her death @1839. So for me, documenting this woman's ownership of slaves has been a challenge. Had it not been for her estate records and subsequent sale of the slaves, I would never have pieced together this little bit on this African American slave owning family.