There is one vital circumstance the agency needs to prove in this scenario: Hemraj's presence in Aarushi's room. For if he wasn't there, there couldn't have been "grave and sudden provocation so how could the murders have taken place at all? This is the question the defence asked as it began its final arguments in the trial court in Ghaziabad. The Talwar's counsel Tanveer Ahmed Mir pointed that after more than a year's attempts (some of them ridiculously ham-handed), and 39 witnesses (many of them distinctly dubious) the CBI had failed to place a single piece of evidence to support the one pillar that held up its edifice: the agency has failed to provide anything that locates Hemraj in Aarushi's room on the night of the murders. No DNA, no blood, no fingerprints, nothing. http://www.sify.com/news/what-is-the-integrity-of-the-aarushi-case-news-columns-nkzgQIdjhfj.html