What you can look for is behavior...do they continue to do the same thing or is there a real change of behavior?
ISTPs look for this as well..after all...all that really matters is what you do, not what you say. For ISTPs talk is not only cheap, it's worthless...unless its funny, then it's priceless.
Unfortunately, ISTPs are not very sympathetic in front of jurors...they just don't show their emotions. And they are impatient to get on with life.