>If there was frost on the ground, as you say the police say then why is it not shown on the ground in the photos taken early on the 26th. before the tempersture rose above freezing?

It's awfully hard to photograph frost. You'd need a really close-up shot. The photos released by Smit show full sunlight, so they could not have been taken all that early. The policeman reported frost. There's no reason to doubt his testimony. Unless you really want to argue the police were already "setting up" the Ramseys as early as 6AM on the 26th.

>When did the police observe this frost? At 6:15 am as officer R. walked the house perimeter?

I think Reichenback arrived roughly around that time, yes.

>Does this mean they are certain the crime wasn't committed before the frost formed? And when was it formed? Frost only forms under certain conditions, which are somewhat different from those when snow is formed.

No one has claimed the absence of prints in the frost is in itself proof positive there was no intruder. But the fact that there was a layer of frost AND no prints were found in it by the officer IS evidence. It DOES have a bearing on the question of whether there could have been an intruder. When it is combined with other evidence, i.e., lack of any sign of disturbance around the window grate, no other prints found ANYWHERE, either in the snow, frost OR turf, no disturbance of the heavy layer of dirt on the sill and frame of the basement window, then ALL this evidence DOES add up to the conclusion that an intruder is unlikely. The problem is that most armchair investigators tend to get caught up in the details and fail to see the big picture. You can argue forever about what Reichenbach's report on the lack of prints in the frost actually means, but when you consider the PREPONDERANCE of evidence the conclusion is not difficult to make.