Without more details on what those 'personal finances' are, I really am not sure what to say, after all, submitting your expenses is standard practice for pretty much anyone else, especially when that money is coming from the Taxpayers' pocket, it was a failure in that system that led to the UK's expenses scandal, but then I can understand if it is stuff like personal bank details etc.
I suppose what concerns me is that this is as much about keeping officers alive as about funding, if an officer is recieving bribes or is a 'bad cop', then that not only compromises the Force itself, but places at risk the lives of other officers, it might be an invasion of personal privacy, but then, I'm not sure whether the Police are as heavily funded by the Government in the US as they are in the UK.