Are 'scrupulous' and 'meticulous' interchangeable in both of these examples?
Scrupulous means thorough, exact, and careful about details.
"Both readers commend Knutson for his scrupulous attention to detail."

If you describe someone as meticulous, you mean that they do things very carefully and with great attention to detail.
"He was so meticulous about everything"

Question

Are 'scrupulous' and 'meticulous' interchangeable in both of these examples?
Scrupulous means thorough, exact, and careful about details.
"Both readers commend Knutson for his scrupulous attention to detail."

If you describe someone as meticulous, you mean that they do things very carefully and with great attention to detail.
"He was so meticulous about everything"

Answer

Scrupulous can also mean "careful [in all details or on all occasions] to avoid wrong doing (in a moral sense)". In the second example, without more of a context, scrupulous would have this meaning. 
"Meticulous" would mean the same as "scrupulous" in the first example.

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