Conclusion

There were political affliations on the Fairfax County Court. While these merchants versus planters can be seen as early as 1759, the issues become more and more prominent with the incorporation of Alexandria and the creation of their mayor-council governing system. With several justices sitting both on the Alexandria Council and Fairfax County Court at times, there's bound to be a conflict of interest. It's unclear whether or not it was prohibited to be on both governing bodies at the same time, since the focus here is Fairfax, and not Alexandria. However, overlap was briefly noticed.

How these political affliations affected votes on issues like levying taxes isn't clear. Justices like William Lyles, a merchant, voted against the 1789 tax issue when the other merchants on the court voted for it. Further research would be required to answer that question. It doesn't look like the affilations of planters and merchants affected when or if a justice came to sit on the court, so some of the justices of the peace were simply more dedicated than others.