on shaky ground

on shaky ground

Questionable or lacking support, as of an idea. His hypothesis has been on shaky ground to since the beginning, so I'm not surprised that he couldn't prove it in the lab.
See also: ground, on, shaky
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

on shaky ground

 and on dangerous ground
Fig. [of an idea or proposal] on an unstable or questionable foundation; [of an idea or proposal] founded on a risky premise. When you suggest that we are to blame, you are on shaky ground. There is no evidence that we are at fault. The case for relying solely on nuclear energy seems to be on dangerous ground.
See also: ground, on, shaky
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
See also:
References in periodicals archive ?
USD-JPY bulls will likely stay cautious, however, as global growth sentiment remains on shaky ground, as as trade concerns continue.
Always on shaky ground scientifically, advocates of the intelligent-design movement officially entered the Twilight Zone after a federal court ruled against them in Dover, Pa.
However, in some chapters the authors have drawn excessively on anecdotal and dated research thus leaving parts of their argument on shaky ground. Scholars looking for strong empirical support for the book's arguments will be disappointed if not all together skeptical.
In the early 90's, the combination of the S&L crisis and a local market slump had put the co-op market on shaky ground, according to Susan Hewlit, Cheshire's founder and president.