Submitted: June 27, 2014 
Court Below: Superior Court of the State of Delaware in and for Sussex County Cr. ID No. 1206017104
Before STRINE, Chief Justice, HOLLAND and VALIHURA, Justices.
LEO E. STRINE, JR. CHIEF JUSTICE
This 19th day of September 2014, upon consideration of the parties' briefs and the Superior Court record, it appears to the Court that:
(1) The appellant, Erik Grandelli ("Grandelli"), filed this appeal from his conviction and sentencing in the Superior Court on his second violation of probation ("VOP"). The background of this matter is as follows.
(2) On September 12, 2012, Grandelli pled guilty to Driving under the Influence (Fourth Offense). The Superior Court sentenced Grandelli to five years at Level V suspended after six months for eighteen months at Level III probation with "zero tolerance for alcohol" use.
(3) On April 18, 2013, Grandelli was charged with his first VOP. The violation report alleged that, during a home visit on April 11, 2013, Grandelli took a breathalyzer test that registered a blood alcohol content of .202% in violation of the "zero tolerance for alcohol" condition of his sentence.
(4) On April 25, 2013, the Superior Court found Grandelli guilty of VOP and resentenced him to four years and four months at Level V suspended for eighteen months at Level III probation. The court reimposed the "zero tolerance for alcohol" condition and added a new condition that Grandelli be monitored with a transdermal alcohol device ("TAD") to detect any alcohol consumption.
(5) On June 20, 2013, Grandelli was charged with his second VOP. The violation report alleged that, on June 17, 2013, Grandelli's TAD detected a "drinking event" that was confirmed on June 18, 2013. On September 5, 2013, the Superior Court found Grandelli guilty of VOP and resentenced him to four years at Level V suspended after successful completion of the Reflections Program for one year at Level III probation. The court also reimposed the "zero tolerance" and TAD monitoring conditions. This appeal followed.
(6) On appeal, Grandelli claims that his second VOP conviction should be overturned because one of the State's witnesses "withheld key evidence" and "was biased [and] clearly presented a conflict of interest." Also, Grandelli claims that the Superior Court abused its discretion "by not considering the 'preponderance of evidence' [and by] passing judgment with a closed mind."
(7) At the VOP hearing, David Smith, Grandelli's probation officer, testified that he and another officer, in conjunction with BI Incorporated (hereinafter "BI"), are responsible for installing and overseeing TAD monitoring in Sussex County. Smith explained that a TAD consists of a transmitter that the probationer wears around his ankle, and a receiver that attaches to the probationer's home telephone. According to Smith, information from the transmitter is downloaded into the receiver at regular intervals and sent over the telephone network to a computer at Smith's office. Smith explained that when he receives an email alert of an event indicating that a probationer has consumed alcohol, he does a preliminary review of the scope and duration of the event and then asks BI to analyze the data and confirm whether the event was a drinking event or a false positive.
(8) Smith testified that he received alerts from Grandelli's TAD on June 12 and June 17, 2013. According to Smith, BI concluded that the June 12 event was a false positive, but that the June 17 event was a drinking event. Smith testified that when Grandelli reported to the office on June 19, 2013 for his regular visit, Smith arrested him and charged him with VOP for having consumed alcohol in violation of the "zero tolerance" condition of his sentence.
(9) Todd Bloemendaal, a BI engineer involved in the development and programming of TADs, testified that a TAD is designed to be calibrated every six months, and that Grandelli's TAD was last calibrated on May 20, 2013, less than a month before the June 17, 2013 alert. Bloemendaal further testified that, in his opinion, Grandelli's TAD was functioning properly on June 17, 2013. Finally, using BI-prepared graphs that depicted the data logged from Grandelli's TAD on June 17, 2013, Bloemendaal testified that the ...