PPRuNe Radar, I'm all for TCAS, but IMHO it is not the answer to everything as some seem to think! As 5milesbaby correctly says, I was not saying pilots should ignore TCAS RAs (although with unverified data the situation still applies)... what I'm suggesting is the pilot should IMHO not be using TCAS to maintain separation and should have taken the avoiding action... unless he was visual with the conflictor or had flight conditions that gave him him a good chance of spotting the traffic early... and leave TCAS to resolve the confliction if both he and I screw up!!!
5milesbaby... Tes, I told the pilot it was unverified and in fact repeated it when he said he was happy to continue because his TCAS was showing it below him. Confliction passed we discussed the situation over the radio, and I got the firm impression the pilot didn't fully understand what unverified meant and the implications of that.
Bookworm, Agree and no I cannot be 100% confident the pilot was in cloud, but weather conditions and the level at which the encounter occurred strongly suggest he was either in cloud or in and out of it... Shall we say, unlikely to be conditions in which visual sighting could be acheived? But, my point is the pilot doesn't know/didn't react to the fact the information was unverified... so I humbly suggest the prevailing Flight Conditions are irrelevant.