To evaluate the expression \(-3 |x| + 2x - 1\) when \(x = -5\), we first need to calculate \(|x|\):
\[ |x| = |-5| = 5 \]
Now, we substitute \(x = -5\) and \(|x| = 5\) into the expression:
\[ -3 |x| + 2x - 1 = -3(5) + 2(-5) - 1 \]
Calculating each term step-by-step:
- \(-3(5) = -15\)
- \(2(-5) = -10\)
Now substituting these values back into the expression:
\[ -15 - 10 - 1 = -26 \]
Thus, the value of the expression \(-3 |x| + 2x - 1\) when \(x = -5\) is \(\boxed{-26}\).