Purity: Ruling on Doubt About Fluid After Time Has Passed Without Istibrāʾ
Practical Laws of Islam as per the teaching of Ayatullah Sistani
Ruling 72
If someone who has not performed istibrāʾ becomes confident that no urine is left in the urethra due to the passing of time since he urinated, and if he then sees some fluid and doubts whether it is pure or not, that fluid is pure and it does not invalidate his wuḍūʾ either.
-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)