1. being watched or examined closely
come under close scrutiny
Something 'under scrutiny' is being examined or monitored in a critical way. Similarly 'under the microscope' means to examine something or to analyse it closely. Both of these phrases have a negative connotation. When you put something 'under the microscope' or 'under scrutiny' it is usually because you expect to find something wrong with it. These expressions can be used as verbs or adverbs.