They *can* legally try to verify it: they may legally call your prior employer and ask them what the salary was (of course, even if they do, they can't make the former employer answer, if the former employer chooses to not); or they could require you to bring in a pay stub or W-2 or other proof of prior salary. If they do and find out that you lied, they could terminate you for cause and/or simply not start you, if you did not start working yet, since you committed fraud (lied about something material or important, to get them to employ you).Whether they *will* or not is impossible to say: some companies and some HR departments verify salary, some do not. My wife is in HR and has worked for three corporate ad/communications firms; only one of those three verified salary in this way, for example.