Besides loving that answer (law school training...) you might be able to fix problem yourself, or it might take dealer.. Common causs of leaks are something getting "stuck" in edges of valve, which slides to close. If something (like TP or worse) gets stuck in groove, valve slider won't close all the way. If you want to try, AND you have place to work on it without making major sanitary mess, you could try combination of back flush with hose towards open valve, while moving it back and forth (with helper) and also use lubricant from RV supply place to assure it closes all the way. Long handled wire brush or other "tool" to dislodge anything stuck in valve body might help, but remember that all it touches is plastic...
If that fails, then valve may have cracked or a plastic piece may have broken, and a replacement would be required. You might be able to do that also (degree in rocket science not required..) but it is hard to work on and messy also..
In Theory, there's no difference between Theory and Practice, but in Practice, there is usually a difference...