jump to conclusions

Fig. to judge or decide something without having all the facts; to reach unwarranted conclusions. (See also rush to conclusions.) Now don't jump to conclusions. Wait until you hear what I have to say. Please find out all the facts so you won't leap to conclusions.

to guess the facts about a situation without having enough information I might be jumping to conclusions but I've seen them together twice in town.

to judge a situation without enough information about it The investigation isn't finished, so let's not jump to conclusions about what caused the plane to crash.