The case against her will be very circumstantial,
This is always said as if such evidence is inferior to eye-witness testimony.
"Circumstantial evidence" is any testimony, exhibit, or evidence that infers guilt on the part of the defendant, this includes things like all forensic evidence (DNA, blood splatter, hair, semen, fingerprints, etc), and testimony about the actions, attitude, behavior, and/or statements of the accused. Bank records, insurance policies, diaries, emails, web browser caches, phone records, and much more can also be introduced as "circumstantial evidence" which helps establish, means, motive and opportunity.
The record of my handgun purchase, the ballistics test matching my handgun to the bullet in the victim, the browser cache showing that someone on a computer in my house visited a site about "assassination methods" with a firearm, the email sent from my email account expressing my hatred of the victim, the presence of blood, and other tissue matched via DNA testing on my clothes, the tests which show my gun has been recently fired and that residue on mt hands indicates that I have discharged a firearm; all of this is circumstantial evidence. Yet, if you were sitting on a jury, you would have an easy time reaching a verdict, even in the absence of "direct evidence".
Direct evidence, usually eye-witness testimony of the crime, is considered more "valid", yet it is usually the least reliable, especially in cases where the accused is a stranger to the witness.
In many cases, circumstantial evidence is far more compelling that direct evidence.