Question number 1: No
There is a good rule of thumb:
If a competitor can do it to you then it is not harmful to you.
Here is why: There are many sketchy places you could get links to a competitor which would then give you control over their reputation without their say.
Question number 2: Also no but sometimes yes! (read below)
This one is a little different. Getting a link from a questionable source is not bad for you as described above, however if you reciprocally link back to that source then you may be vulnerable to being penalized by google if the site linking to you has been penalized. It is your responsibility to make sure you do not vote to bad neighbourhoods.
To further answer question 2, if you are reciprocally linking to a bad neighborhood and also linking out to another site your outgoing link can only be harmful if that site reciprocally links back to you.
So as long as your follow the answer above for question 1 then there will be no trouble 
Hope this helps.