To believe wrongly that someone or something has the same bad qualities as someone or something that is similar (usually passive)
Acreditar equivocadamente que alguém ou algo possui as mesas qualidades ruins que um outro alguém ou algo parececido.
Ex: I admit that some football supporters do cause trouble but it's not fair that we're all beign tarred with the same brush.
Na frase acima parece estar com o sentido de "tachados de maneira equivocada"
From David Fosse: I used the phrase, tarred with the same brush recently, meaning, guilty of the same behavior, or acting in the same manner as someone else, or likely to be considered the same as someone http://www.worldwidewords.org/qa/qa-tar1.htm
Having the same faults or bad qualities as in He may be lazy, but if you ask me his friends are all tarred with the same bush
If people are tarred with the same brush, they're to said to have the same set of attributes or faults as someone they are associated with
From: http://www.usingenglish.com/reference/i ... brush.html
To characterize using the same undesirable attribute, especiallu unjustly