This courthouse still remains in the town square and would by most reckonings still be considered the county courthouse. However, the county court (admin) and the district courts (criminal) no longer meet in the building. It is now the community performing arts center. The original courtroom is now the theater. Ingenious, really. It still serves as an important part of the community. I was told that once a year a judge does come to the theater and hold court. It is entirely reconstructed for that one day. So maybe, based on that single event, it is still the courthouse of Collin County. The new courthouse is a well-done modern edifice on the outside of McKinney.
It should be noted that the1979 courthouse was abandoned and torn town. Hate to say it, but probably not a big loss. The building was a non-descript modern building with little heart nor soul.
The historic courthouse was actually built in 1874 and was a Second Empire design, with Charles Wheeler serving as the architect. It was TOTALLY redesigned in 1927 by the architect W. A. Peters. The style leans toward classical revival or Texas Renaissance. Either way, it’s not particulary attractive, but is an important part of McKinney and Collin County. When restored, the building was taken back to the 1927 remodeling. Far too much of the 1874 building was lost.