During the pandemic, the EPO introduced a ViCo oral proceedings pilot program, whereby all opposition and examining division oral proceedings were to be held by ViCo. The mandatory use of ViCo oral proceedings was introduced in response to the travel restrictions caused by the COVID-19 pandemic, which prevented most people from attending proceedings in-person at the EPO. Thus it is up to the relevant EPO division to decide whether the use of ViCo permits an adequate assessment. Importantly, the Board of Appeal also noted that it is the responsibility of the deciding division of the EPO to make a judgement about the witness's credibility. ViCo was therefore found to be a perfectly sufficient format for witness testimony, even when the entire outcome of a case rested on the witness evidence.
The Board of Appeal concluded that body language is only ever a small part of an assessment of witness credibility. The Board of Appeal in T 423/22 considered whether a witness's credibility can be adequately assessed when proceedings are conducted by video conference (ViCo).
